Circuits for controlling display apparatus

Information

  • Patent Grant
  • 9082353
  • Patent Number
    9,082,353
  • Date Filed
    Tuesday, January 5, 2010
    14 years ago
  • Date Issued
    Tuesday, July 14, 2015
    8 years ago
Abstract
The invention relates to methods and apparatus for forming images on a display utilizing a control matrix to control the movement of MEMS-based light modulators.
Description
FIELD OF THE INVENTION

In general, the invention relates to the field of imaging displays, in particular, the invention relates to controller circuits and processes for controlling light modulators incorporated into imaging displays.


BACKGROUND OF THE INVENTION

Displays built from mechanical light modulators are an attractive alternative to displays based on liquid crystal technology. Mechanical light modulators are fast enough to display video content with good viewing angles and with a wide range of color and grey scale. Mechanical light modulators have been successful in projection display applications. Direct-view displays using mechanical light modulators have not yet demonstrated sufficiently attractive combinations of brightness and low power. There is a need in the art for fast, bright, low-powered mechanically actuated direct-view displays. Specifically there is a need for direct-view displays that can be driven at high speeds and at low voltages for improved image quality and reduced power consumption.


In contrast to projection displays in which switching circuitry and light modulators can be built on relatively small die cut from silicon substrates, most direct-view displays require the fabrication of light modulators on much larger substrates. In addition, in many cases, particularly for backlit direct view displays, both the control circuitry and the light modulators are preferably formed on transparent substrates. As a result, many typical semiconductor manufacturing processes are inapplicable. New switching circuits and control algorithms often need to be developed to address the fundamental differences in materials, process technology, and performance characteristics of MEMS devices built on transparent substrates. A need remains for MEMS direct-view displays that incorporate modulation processes in conjunction with switching circuitry that yield detailed images along with rich levels of grayscale and contrast.


SUMMARY

The invention relates to direct-view display apparatuses including an array of pixels. The array of pixels include, for each pixel, a MEMS-based light modulator formed on a substrate, and a first actuator and a second actuator opposing the first actuator for controlling the state of the light modulator to form an image on the display apparatus. In certain embodiments, the array of pixels include a control matrix disposed on the substrate which includes a dual inverter latch coupling the first and second actuators and configured to maintain an opposite logical state on the first and second actuators. In some embodiments, the substrate is a transparent substrate.


In one aspect of the invention, the dual inverter latch includes two cross-coupled inverters. In some embodiments, the two cross-coupled inverters may include two transistors, dual gate transistors, may be connected to a cascode circuit, or any combination thereof.


In some embodiments, the display apparatus includes a data store in which the dual inverter latch is latched in the first state based, at least in part, on a data voltage stored in the data store. In certain embodiments, the display apparatus includes a switch coupling the data store to the dual inverter latch for allowing the data to pass from the data store to the dual inverter latch. In one aspect, the switch is controlled by a common voltage interconnect for a plurality of rows and columns. In certain embodiments, the switch functions to electrically de-couple the data store from the dual inverter latch to prevent current from flowing between the data store and the dual inverter latch.


In some embodiments, the display apparatus includes an actuation line interconnect. In one aspect, the actuation line interconnect is configured to provide a voltage to only one of the first and second actuators for actuating the light modulator to form an image. In some embodiments, the actuation line interconnect provides an intermediate voltage to latch the dual inverter latch in a first state corresponding to the data voltage.


In certain embodiments, the invention relates to a method for addressing pixels in a display in which each pixel includes a MEMS based light modulator, first and second actuators, and a dual inverter latch coupling the first and second actuators for maintaining an opposite logical state on the first and second actuators. The method includes loading data into a data store coupled to the dual inverter latch, updating the latch state based at least in part on the loaded data such that a full actuation voltage is only applied to one of the first and second actuators, and actuating the MEMS based light modulator. In one aspect, actuating the MEMS-based light modulator includes applying voltages to the MEMS-based light modulator and to the first and second actuators in accordance with a polarity reversal process.





BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing discussion will be understood more readily from the following detailed description of the invention with reference to the following drawings:



FIG. 1A is an isometric view of display apparatus, according to an illustrative embodiment of the invention;



FIG. 1B is a block diagram of the display apparatus of FIG. 1A, according to an illustrative embodiment of the invention;



FIG. 1C is a timing diagram for a method of displaying an image on a display using a field sequential color technique, according to an illustrative embodiment of the invention;



FIG. 1D is a timing diagram illustrating the timing of various image formation events using a coded time division grayscale technique, according to an illustrative embodiment of the invention;



FIG. 2A is a perspective view of an illustrative shutter-based light modulator suitable for incorporation into the MEMS-based display of FIG. 1A, according to an illustrative embodiment of the invention;



FIG. 2B is a cross-sectional view of a rollershade-based light modulator suitable for incorporation into the MEMS-based display of FIG. 1A, according to an illustrative embodiment of the invention;



FIG. 2C is a cross sectional view of a light-tap-based light modulator suitable for incorporation into an alternative embodiment of the MEMS-based display of FIG. 1A, according to an illustrative embodiment of the invention;



FIG. 2D is a cross sectional view of an electrowetting-based light modulator suitable for incorporation into an alternative embodiment of the MEMS-based display of FIG. 1A, according to an illustrative embodiment of the invention;



FIG. 3A is a schematic diagram of a control matrix suitable for controlling the light modulators incorporated into the MEMS-based display of FIG. 1A, according to an illustrative embodiment of the invention;



FIG. 3B is a perspective view of an array of shutter-based light modulators connected to the control matrix of FIG. 3A, according to an illustrative embodiment of the invention;



FIGS. 4A and 4B are plan views of a dual-actuated shutter assembly in the open and closed states respectively, according to an illustrative embodiment of the invention;



FIG. 4C is a cross sectional view of a dual actuator light tap-based light modulator suitable for incorporation into the MEMS-based display, according to an illustrative embodiment of the invention;



FIG. 5A is a diagram of a control matrix suitable for controlling the shutter assemblies of the display apparatus of FIG. 1A, according to an illustrative embodiment of the invention;



FIG. 5B is a flow chart of a method of addressing the pixels of the control matrix of FIG. 5A, according to an illustrative embodiment of the invention;



FIG. 6 is a diagram of a control matrix suitable for controlling the shutter assemblies of the display apparatus of FIG. 1A, according to an illustrative embodiment of the invention;



FIG. 7 is a diagram of a control matrix suitable for controlling the shutter assemblies of the display apparatus of FIG. 1A, according to an illustrative embodiment of the invention;



FIG. 8 is a diagram of a control matrix suitable for controlling the shutter assemblies of the display apparatus of FIG. 1A, according to an illustrative embodiment of the invention;



FIG. 9A is a chart of voltage variations vs. time during pixel operation, according to an illustrative embodiment of the invention;



FIG. 9B is a chart of voltage transition detail during pixel actuation, according to an illustrative embodiment of the invention;



FIG. 10A is a chart of the voltage increase on an actuator node during pixel operation, according to an illustrative embodiment of the invention;



FIG. 10B is a chart of the latch current transient of the coupled transistors during pixel operation, according to an illustrative embodiment of the invention;



FIG. 11A is a chart of the voltage increase on an actuator node during pixel operation, according to an illustrative embodiment of the invention;



FIG. 11B is a chart of the latch current transient of the coupled transistors during pixel operation, according to an illustrative embodiment of the invention;





DESCRIPTION OF CERTAIN ILLUSTRATIVE EMBODIMENTS

To provide an overall understanding of the invention, certain illustrative embodiments will now be described, including apparatus and methods for displaying images. However, it will be understood by one of ordinary skill in the art that the systems and methods described herein may be adapted and modified as is appropriate for the application being addressed and that the systems and methods described herein may be employed in other suitable applications, and that such other additions and modifications will not depart from the scope hereof.



FIG. 1 is a schematic diagram of a direct-view MEMS-based display apparatus 100, according to an illustrative embodiment of the invention. The display apparatus 100 includes a plurality of light modulators 102a-102d (generally “light modulators 102”) arranged in rows and columns. In the display apparatus 100, light modulators 102a and 102d are in the open state, allowing light to pass. Light modulators 102b and 102c are in the closed state, obstructing the passage of light. By selectively setting the states of the light modulators 102a-102d, the display apparatus 100 can be utilized to form an image 104 for a backlit display, if illuminated by a lamp or lamps 105. In another implementation, the apparatus 100 may form an image by reflection of ambient light originating from the front of the apparatus. In another implementation, the apparatus 100 may form an image by reflection of light from a lamp or lamps positioned in the front of the display, i.e. by use of a frontlight. In one of the closed or open states, the light modulators 102 interfere with light in an optical path by, for example, and without limitation, blocking, reflecting, absorbing, filtering, polarizing, diffracting, or otherwise altering a property or path of the light.


In the display apparatus 100, each light modulator 102 corresponds to a pixel 106 in the image 104. In other implementations, the display apparatus 100 may utilize a plurality of light modulators to form a pixel 106 in the image 104. For example, the display apparatus 100 may include three color-specific light modulators 102. By selectively opening one or more of the color-specific light modulators 102 corresponding to a particular pixel 106, the display apparatus 100 can generate a color pixel 106 in the image 104. In another example, the display apparatus 100 includes two or more light modulators 102 per pixel 106 to provide grayscale in an image 104. With respect to an image, a “pixel” corresponds to the smallest picture element defined by the resolution of the image. With respect to structural components of the display apparatus 100, the term “pixel” refers to the combined mechanical and electrical components utilized to modulate the light that forms a single pixel of the image.


Display apparatus 100 is a direct-view display in that it does not require imaging optics. The user sees an image by looking directly at the display apparatus 100. In alternate embodiments the display apparatus 100 is incorporated into a projection display. In such embodiments, the display forms an image by projecting light onto a screen or onto a wall. In projection applications the display apparatus 100 is substantially smaller than the projected image 104.


Direct-view displays may operate in either a transmissive or reflective mode. In a transmissive display, the light modulators filter or selectively block light which originates from a lamp or lamps positioned behind the display. The light from the lamps is optionally injected into a light guide or “backlight”. Transmissive direct-view display embodiments are often built onto transparent or glass substrates to facilitate a sandwich assembly arrangement where one substrate, containing the light modulators, is positioned directly on top of the backlight. In some transmissive display embodiments, a color-specific light modulator is created by associating a color filter material with each modulator 102. In other transmissive display embodiments colors can be generated, as described below, using a field sequential color method by alternating illumination of lamps with different primary colors.


Each light modulator 102 includes a shutter 108 and an aperture 109. To illuminate a pixel 106 in the image 104, the shutter 108 is positioned such that it allows light to pass through the aperture 109 towards a viewer. To keep a pixel 106 unlit, the shutter 108 is positioned such that it obstructs the passage of light through the aperture 109. The aperture 109 is defined by an opening patterned through a reflective or light-absorbing material.


The display apparatus also includes a control matrix connected to the substrate and to the light modulators for controlling the movement of the shutters. The control matrix includes a series of electrical interconnects (e.g., interconnects 110, 112, and 114), including at least one write-enable interconnect 110 (also referred to as a “scan-line interconnect”) per row of pixels, one data interconnect 112 for each column of pixels, and one common interconnect 114 providing a common voltage to all pixels, or at least to pixels from both multiple columns and multiples rows in the display apparatus 100. In response to the application of an appropriate voltage (the “write-enabling voltage, Vwe”), the write-enable interconnect 110 for a given row of pixels prepares the pixels in the row to accept new shutter movement instructions. The data interconnects 112 communicate the new movement instructions in the form of data voltage pulses. The data voltage pulses applied to the data interconnects 112, in some implementations, directly contribute to an electrostatic movement of the shutters. In other implementations, the data voltage pulses control switches, e.g., transistors or other non-linear circuit elements that control the application of separate actuation voltages, which are typically higher in magnitude than the data voltages, to the light modulators 102. The application of these actuation voltages then results in the electrostatic driven movement of the shutters 108.



FIG. 1B is a block diagram 150 of the display apparatus 100. Referring to FIGS. 1A and 1B, in addition to the elements of the display apparatus 100 described above, as depicted in the block diagram 150, the display apparatus 100 includes a plurality of scan drivers 152 (also referred to as “write enabling voltage sources”) and a plurality of data drivers 154 (also referred to as “data voltage sources”). The scan drivers 152 apply write enabling voltages to scan-line interconnects 110. The data drivers 154 apply data voltages to the data interconnects 112. In some embodiments of the display apparatus, the data drivers 154 are configured to provide analog data voltages to the light modulators, especially where the gray scale of the image 104 is to be derived in analog fashion. In analog operation the light modulators 102 are designed such that when a range of intermediate voltages is applied through the data interconnects 112 there results a range of intermediate open states in the shutters 108 and therefore a range of intermediate illumination states or gray scales in the image 104.


In other cases the data drivers 154 are configured to apply only a reduced set of 2, 3, or 4 digital voltage levels to the control matrix. These voltage levels are designed to set, in digital fashion, either an open state or a closed state to each of the shutters 108.


The scan drivers 152 and the data drivers 154 are connected to digital controller circuit 156 (also referred to as the “controller 156”). The controller 156 includes an input processing module 158, which processes an incoming image signal 157 into a digital image format appropriate to the spatial addressing and the gray scale capabilities of the display 100. The pixel location and gray scale data of each image is stored in a frame buffer 159 so that the data can be fed out as needed to the data drivers 154. The data is sent to the data drivers 154 in mostly serial fashion, organized in predetermined sequences grouped by rows and by image frames. The data drivers 154 can include series to parallel data converters, level shifting, and for some applications digital to analog voltage converters.


The display 100 apparatus optionally includes a set of common drivers 153, also referred to as common voltage sources. In some embodiments the common drivers 153 provide a DC common potential to all light modulators within the array of light modulators 103, for instance by supplying voltage to a series of common interconnects 114. In other embodiments the common drivers 153, following commands from the controller 156, issue voltage pulses or signals to the array of light modulators 103, for instance global actuation pulses which are capable of driving and/or initiating simultaneous actuation of all light modulators in multiple rows and columns of the array 103.


All of the drivers (e.g., scan drivers 152, data drivers 154, and common drivers 153) for different display functions are time-synchronized by a timing-control module 160 in the controller 156. Timing commands from the module 160 coordinate the illumination of red, green and blue and white lamps (162, 164, 166, and 167 respectively) via lamp drivers 168, the write-enabling and sequencing of specific rows within the array of pixels 103, the output of voltages from the data drivers 154, and the output of voltages that provide for light modulator actuation.


The controller 156 determines the sequencing or addressing scheme by which each of the shutters 108 in the array 103 can be re-set to the illumination levels appropriate to a new image 104. Details of suitable addressing, image formation, and gray scale techniques can be found in U.S. patent application Ser. Nos. 11/326,696 and 11/643,042, incorporated herein by reference. New images 104 can be set at periodic intervals. For instance, for video displays, the color images 104 or frames of video are refreshed at frequencies ranging from 10 to 300 Hertz. In some embodiments the setting of an image frame to the array 103 is synchronized with the illumination of the lamps 162, 164, and 166 such that alternate image frames are illuminated with an alternating series of colors, such as red, green, and blue. The image frames for each respective color is referred to as a color sub-frame. In this method, referred to as the field sequential color method, if the color sub-frames are alternated at frequencies in excess of 20 Hz, the human brain will average the alternating frame images into the perception of an image having a broad and continuous range of colors. In alternate implementations, four or more lamps with primary colors can be employed in display apparatus 100, employing primaries other than red, green, and blue.


In some implementations, where the display apparatus 100 is designed for the digital switching of shutters 108 between open and closed states, the controller 156 determines the addressing sequence and/or the time intervals between image frames to produce images 104 with appropriate gray scale. The process of generating varying levels of grayscale by controlling the amount of time a shutter 108 is open in a particular frame is referred to as time division gray scale. In one embodiment of time division gray scale, the controller 156 determines the time period or the fraction of time within each frame that a shutter 108 is allowed to remain in the open state, according to the illumination level or gray scale desired of that pixel. In other implementations, for each image frame, the controller 156 sets a plurality of sub-frame images in multiple rows and columns of the array 103, and the controller alters the duration over which each sub-frame image is illuminated in proportion to a gray scale value or significance value employed within a coded word for gray scale. For instance, the illumination times for a series of sub-frame images can be varied in proportion to the binary coding series 1, 2, 4, 8 . . . . The shutters 108 for each pixel in the array 103 are then set to either the open or closed state within a sub-frame image according to the value at a corresponding position within the pixel's binary coded word for gray level.


In other implementations, the controller alters the intensity of light from the lamps 162, 164, and 166 in proportion to the gray scale value desired for a particular sub-frame image. A number of hybrid techniques are also available for forming colors and gray scale from an array of shutters 108. For instance, the time division techniques described above can be combined with the use of multiple shutters 108 per pixel, or the gray scale value for a particular sub-frame image can be established through a combination of both sub-frame timing and lamp intensity. Details of these and other embodiments can be found in U.S. patent application Ser. No. 11/643,042, referenced above.


In some implementations the data for an image state 104 is loaded by the controller 156 to the modulator array 103 by a sequential addressing of individual rows, also referred to as scan lines. For each row or scan line in the sequence, the scan driver 152 applies a write-enable voltage to the write enable interconnect 110 for that row of the array 103, and subsequently the data driver 154 supplies data voltages, corresponding to desired shutter states, for each column in the selected row. This process repeats until data has been loaded for all rows in the array. In some implementations the sequence of selected rows for data loading is linear, proceeding from top to bottom in the array. In other implementations the sequence of selected rows is pseudo-randomized, in order to minimize visual artifacts. And in other implementations the sequencing is organized by blocks, where, for a block, the data for only a certain fraction of the image state 104 is loaded to the array, for instance by addressing only every 5th row of the array in sequence.


In some implementations, the process for loading image data to the array 103 is separated in time from the process of actuating the shutters 108. In these implementations, the modulator array 103 may include data memory elements for each pixel in the array 103 and the control matrix may include a global actuation interconnect for carrying trigger signals, from common driver 153, to initiate simultaneous actuation of shutters 108 according to data stored in the memory elements. Various addressing sequences, many of which are described in U.S. patent application Ser. No. 11/643,042, can be coordinated by means of the timing control module 160.


In alternative embodiments, the array of pixels 103 and the control matrix that controls the pixels may be arranged in configurations other than rectangular rows and columns. For example, the pixels can be arranged in hexagonal arrays or curvilinear rows and columns. In general, as used herein, the term scan-line shall refer to any plurality of pixels that share a write-enabling interconnect.


The display 100 is comprised of a plurality of functional blocks including the timing control module 160, the frame buffer 159, scan drivers 152, data drivers 154, and drivers 153 and 168. Each block can be understood to represent either a distinguishable hardware circuit and/or a module of executable code. In some implementations the functional blocks are provided as distinct chips or circuits connected together by means of circuit boards and/or cables. Alternately, many of these circuits can be fabricated along with the pixel array 103 on the same substrate of glass or plastic. In other implementations, multiple circuits, drivers, processors, and/or control functions from block diagram 150 may be integrated together within a single silicon chip, which is then bonded directly to the transparent substrate holding pixel array 103.


The controller 156 includes a programming link 180 by which the addressing, color, and/or gray scale algorithms, which are implemented within controller 156, can be altered according to the needs of particular applications. In some embodiments, the programming link 180 conveys information from environmental sensors, such as ambient light or temperature sensors, so that the controller 156 can adjust imaging modes or backlight power in correspondence with environmental conditions. The controller 156 also comprises a power supply input 182 which provides the power needed for lamps as well as light modulator actuation. Where necessary, the drivers 152153, 154, and/or 168 may include or be associated with DC-DC converters for transforming an input voltage at 182 into various voltages sufficient for the actuation of shutters 108 or illumination of the lamps, such as lamps 162, 164, 166, and 167.


Field Sequential Color/Time Division Grayscale


The human brain, in response to viewing rapidly changing images, for example, at frequencies of greater than 20 Hz, averages images together to perceive an image which is the combination of the images displayed within a corresponding period. This phenomenon can be utilized to display color images while using only single light modulators for each pixel of a display, using a technique referred to in the art as field sequential color. The use of field sequential color techniques in displays eliminates the need for color filters and multiple light modulators per pixel. In a field sequential color enabled display, an image frame to be displayed is divided into a number of sub-frame images, each corresponding to a particular color component (for example, red, green, or blue) of the original image frame. For each sub-frame image, the light modulators of a display are set into states corresponding to the color component's contribution to the image. The light modulators then are illuminated by a lamp of the corresponding color. The sub-images are displayed in sequence at a frequency (for example, greater than 60 Hz) sufficient for the brain to perceive the series of sub-frame images as a single image. The data used to generate the sub-frames are often fractured in various memory components. For example, in some displays, data for a given row of display are kept in a shift-register dedicated to that row. Image data is shifted in and out of each shift register to a light modulator in a corresponding column in that row of the display according to a fixed clock cycle.



FIG. 1C is a timing diagram corresponding to a display process for displaying images using field sequential color, which can be implemented according to an illustrative embodiment of the invention, for example, by a MEMS direct-view display described in FIG. 1B. The timing diagrams included herein, including the timing diagram of FIG. 1C, conform to the following conventions. The top portions of the timing diagrams illustrate light modulator addressing events. The bottom portions illustrate lamp illumination events.


The addressing portions depict addressing events by diagonal lines spaced apart in time. Each diagonal line corresponds to a series of individual data loading events during which data is loaded into each row of an array of light modulators, one row at a time. Depending on the control matrix used to address and drive the modulators included in the display, each loading event may require a waiting period to allow the light modulators in a given row to actuate. In some implementations, all rows in the array of light modulators are addressed prior to actuation of any of the light modulators. Upon completion of loading data into the last row of the array of light modulators, all light modulators are actuated substantially simultaneously.


Lamp illumination events are illustrated by pulse trains corresponding to each color of lamp included in the display. Each pulse indicates that the lamp of the corresponding color is illuminated, thereby displaying the sub-frame image loaded into the array of light modulators in the immediately preceding addressing event.


The time at which the first addressing event in the display of a given image frame begins is labeled on each timing diagram as AT0. In most of the timing diagrams, this time falls shortly after the detection of a voltage pulse vsync, which precedes the beginning of each video frame received by a display. The times at which each subsequent addressing event takes place are labeled as AT1, AT2, . . . AT(n−1), where n is the number of sub-frame images used to display the image frame. In some of the timing diagrams, the diagonal lines are further labeled to indicate the data being loaded into the array of light modulators. For example, in the timing diagram of FIG. 1C, D0 represents the first data loaded into the array of light modulators for a frame and D(n−1) represents the last data loaded into the array of light modulators for the frame. In the timing diagrams of FIG. 1D, the data loaded during each addressing event corresponds to a bitplane.



FIG. 1D is a timing diagram that corresponds to a coded-time division grayscale display process in which image frames are displayed by displaying four sub-frame images for each of three color components (red, green, and blue) of the image frame. Each sub-frame image displayed of a given color is displayed at the same intensity for half as long a time period as the prior sub-frame image, thereby implementing a binary weighting scheme for the sub-frame images.


The display of an image frame begins upon the detection of a vsync pulse. The first sub-frame data set R3, stored beginning at memory location M0, is loaded into the array of light modulators 103 in an addressing event that begins at time AT0. The red lamp is then illuminated at time LT0. LT0 is selected such that it occurs after each of the rows in the array of light modulators 103 has been addressed, and the light modulators included therein have actuated. At time AT1, the controller 156 of the direct-view display both extinguishes the red lamp and begins loading the subsequent bitplane, R2, into the array of light modulators 103. This bitplane is stored beginning at memory location M1. The process repeats until all bitplanes have been displayed. For example, at time AT4, the controller 156 extinguishes the red lamp and begins loading the most significant green bitplane, G3, into the array of light modulators 103. Similarly at time LT6, the controller 156 turns on the green lamp until time AT7, at which it time it is extinguished again.


The time period between vsync pulses in the timing diagram is indicated by the symbol FT, indicating a frame time. In some implementations the addressing times AT0, AT1, etc. as well as the lamp times LT0, LT1, etc. are designed to accomplish 4 sub-frame images per color within a frame time FT of 16.6 milliseconds, i.e. according to a frame rate of 60 Hz. In other implementations the time values can be altered to accomplish 4 sub-frame images per color within a frame time FT of 33.3 milliseconds, i.e. according to a frame rate of 30 Hz. In other implementations frame rates as low as 24 Hz may be employed or frame rates in excess of 100 Hz may be employed.


In the particular implementation of coded time division gray scale illustrated by the timing diagram in FIG. 1D, the controller outputs 4 sub-frame images to the array 103 of light modulators for each color to be displayed. The illumination of each of the 4 sub-frame images is weighted according to the binary series 1, 2, 4, 8. The display process in the timing diagram of FIG. 1D, therefore, displays a 4-digit binary word for gray scale in each color, that is, it is capable of displaying 16 distinct gray scale levels for each color, despite the loading of only 4 sub-images per color. Through combinations of the colors, the implementation of the timing diagram of FIG. 1D is capable of displaying more than 4000 distinct colors.


MEMS Light Modulators



FIG. 2A is a perspective view of an illustrative shutter-based light modulator 200 suitable for incorporation into the MEMS-based display apparatus 100 of FIG. 1A, according to an illustrative embodiment of the invention. The shutter-based light modulator 200 (also referred to as shutter assembly 200) includes a shutter 202 coupled to an actuator 204. The actuator 204 is formed from two separate compliant electrode beam actuators 205 (the “actuators 205”), as described in U.S. Pat. No. 7,271,945, filed on Sep. 18, 2007. The shutter 202 couples on one side to the actuators 205. The actuators 205 move the shutter 202 transversely over a surface 203 in a plane of motion which is substantially parallel to the surface 203. The opposite side of the shutter 202 couples to a spring 207 which provides a restoring force opposing the forces exerted by the actuator 204.


Each actuator 205 includes a compliant load beam 206 connecting the shutter 202 to a load anchor 208. The load anchors 208 along with the compliant load beams 206 serve as mechanical supports, keeping the shutter 202 suspended proximate to the surface 203. The load anchors 208 physically connect the compliant load beams 206 and the shutter 202 to the surface 203 and electrically connect the load beams 206 to a bias voltage, in some instances, ground.


Each actuator 205 also includes a compliant drive beam 216 positioned adjacent to each load beam 206. The drive beams 216 couple at one end to a drive beam anchor 218 shared between the drive beams 216. The other end of each drive beam 216 is free to move. Each drive beam 216 is curved such that it is closest to the load beam 206 near the free end of the drive beam 216 and the anchored end of the load beam 206.


The surface 203 includes one or more apertures 211 for admitting the passage of light. If the shutter assembly 200 is formed on an opaque substrate, made, for example, from silicon, then the surface 203 is a surface of the substrate, and the apertures 211 are formed by etching an array of holes through the substrate. If the shutter assembly 200 is formed on a transparent substrate, made, for example, of glass or plastic, then the surface 203 is a surface of a light blocking layer deposited on the substrate, and the apertures are formed by etching the surface 203 into an array of holes 211. The apertures 211 can be generally circular, elliptical, polygonal, serpentine, or irregular in shape.


In operation, a display apparatus incorporating the light modulator 200 applies an electric potential to the drive beams 216 via the drive beam anchor 218. A second electric potential may be applied to the load beams 206. The resulting potential difference between the drive beams 216 and the load beams 206 pulls the free ends of the drive beams 216 towards the anchored ends of the load beams 206, and pulls the shutter ends of the load beams 206 toward the anchored ends of the drive beams 216, thereby driving the shutter 202 transversely towards the drive anchor 218. The compliant members 206 act as springs, such that when the voltage across the beams 206 and 216 is removed, the load beams 206 push the shutter 202 back into its initial position, releasing the stress stored in the load beams 206.


The shutter assembly 200, also referred to as an elastic shutter assembly, incorporates a passive restoring force, such as a spring, for returning a shutter to its rest or relaxed position after voltages have been removed. A number of elastic restore mechanisms and various electrostatic couplings can be designed into or in conjunction with electrostatic actuators, the compliant beams illustrated in shutter assembly 200 being just one example. Other examples are described in U.S. Pat. No. 7,271,945 and U.S. patent application Ser. No. 11/326,696, incorporated herein by reference. For instance, a highly non-linear voltage-displacement response can be provided which favors an abrupt transition between “open” vs “closed” states of operation, and which, in many cases, provides a bi-stable or hysteretic operating characteristic for the shutter assembly. Other electrostatic actuators can be designed with more incremental voltage-displacement responses and with considerably reduced hysteresis, as may be preferred for analog gray scale operation.


The actuator 205 within the elastic shutter assembly is said to operate between a closed or actuated position and a relaxed position. The designer, however, can choose to place apertures 211 such that shutter assembly 200 is in either the “open” state, i.e. passing light, or in the “closed” state, i.e. blocking light, whenever actuator 205 is in its relaxed position. For illustrative purposes, it is assumed below that elastic shutter assemblies described herein are designed to be open in their relaxed state.


In many cases it is preferable to provide a dual set of “open” and “closed” actuators as part of a shutter assembly so that the control electronics are capable of electrostatically driving the shutters into each of the open and closed states.


Display apparatus 100, in alternative embodiments, includes light modulators other than transverse shutter-based light modulators, such as the shutter assembly 200 described above. For example, FIG. 2B is a cross-sectional view of a rolling actuator shutter-based light modulator 220 suitable for incorporation into an alternative embodiment of the MEMS-based display apparatus 100 of FIG. 1A, according to an illustrative embodiment of the invention. As described further in U.S. Pat. No. 5,233,459, entitled “Electric Display Device,” and U.S. Pat. No. 5,784,189, entitled “Spatial Light Modulator,” the entireties of which are incorporated herein by reference, a rolling actuator-based light modulator includes a moveable electrode disposed opposite a fixed electrode and biased to move in a preferred direction to produce a shutter upon application of an electric field. In one embodiment, the light modulator 220 includes a planar electrode 226 disposed between a substrate 228 and an insulating layer 224 and a moveable electrode 222 having a fixed end 230 attached to the insulating layer 224. In the absence of any applied voltage, a moveable end 232 of the moveable electrode 222 is free to roll towards the fixed end 230 to produce a rolled state. Application of a voltage between the electrodes 222 and 226 causes the moveable electrode 222 to unroll and lie flat against the insulating layer 224, whereby it acts as a shutter that blocks light traveling through the substrate 228. The moveable electrode 222 returns to the rolled state by means of an elastic restoring force after the voltage is removed. The bias towards a rolled state may be achieved by manufacturing the moveable electrode 222 to include an anisotropic stress state.



FIG. 2C is a cross-sectional view of an illustrative non shutter-based MEMS light modulator 250. The light tap modulator 250 is suitable for incorporation into an alternative embodiment of the MEMS-based display apparatus 100 of FIG. 1A, according to an illustrative embodiment of the invention. As described further in U.S. Pat. No. 5,771,321, entitled “Micromechanical Optical Switch and Flat Panel Display,” the entirety of which is incorporated herein by reference, a light tap works according to a principle of frustrated total internal reflection. That is, light 252 is introduced into a light guide 254, in which, without interference, light 252 is for the most part unable to escape the light guide 254 through its front or rear surfaces due to total internal reflection. The light tap 250 includes a tap element 256 that has a sufficiently high index of refraction that, in response to the tap element 256 contacting the light guide 254, light 252 impinging on the surface of the light guide 254 adjacent the tap element 256 escapes the light guide 254 through the tap element 256 towards a viewer, thereby contributing to the formation of an image.


In one embodiment, the tap element 256 is formed as part of beam 258 of flexible, transparent material. Electrodes 260 coat portions of one side of the beam 258. Opposing electrodes 260 are disposed on the light guide 254. By applying a voltage across the electrodes 260, the position of the tap element 256 relative to the light guide 254 can be controlled to selectively extract light 252 from the light guide 254.



FIG. 2D is a cross sectional view of a second illustrative non-shutter-based MEMS light modulator suitable for inclusion in various embodiments of the invention. Specifically, FIG. 2D is a cross sectional view of an electrowetting-based light modulation array 270. The electrowetting-based light modulator array 270 is suitable for incorporation into an alternative embodiment of the MEMS-based display apparatus 100 of FIG. 1A, according to an illustrative embodiment of the invention. The light modulation array 270 includes a plurality of electrowetting-based light modulation cells 272a-272d (generally “cells 272”) formed on an optical cavity 274. The light modulation array 270 also includes a set of color filters 276 corresponding to the cells 272.


Each cell 272 includes a layer of water (or other transparent conductive or polar fluid) 278, a layer of light absorbing oil 280, a transparent electrode 282 (made, for example, from indium-tin oxide) and an insulating layer 284 positioned between the layer of light absorbing oil 280 and the transparent electrode 282. Illustrative implementations of such cells are described further in U.S. Patent Application Publication No. 2005/0104804, published May 19, 2005 and entitled “Display Device.” In the embodiment described herein, the electrode takes up a portion of a rear surface of a cell 272.


The light modulation array 270 also includes a light guide 288 and one or more light sources 292 which inject light 294 into the light guide 288. A series of light redirectors 291 are formed on the rear surface of the light guide, proximate a front facing reflective layer 290. The light redirectors 291 may be either diffuse or specular reflectors. The modulation array 270 includes an aperture layer 286 which is patterned into a series of apertures, one aperture for each of the cells 272, to allow light rays 294 to pass through the cells 272 and toward the viewer.


In one embodiment the aperture layer 286 is comprised of a light absorbing material to block the passage of light except through the patterned apertures. In another embodiment the aperture layer 286 is comprised of a reflective material which reflects light not passing through the surface apertures back towards the rear of the light guide 288. After returning to the light guide, the reflected light can be further recycled by the front facing reflective layer 290.


In operation, application of a voltage to the electrode 282 of a cell causes the light absorbing oil 280 in the cell to move into or collect in one portion of the cell 272. As a result, the light absorbing oil 280 no longer obstructs the passage of light through the aperture formed in the reflective aperture layer 286 (see, for example, cells 272b and 272c). Light escaping the light guide 288 at the aperture is then able to escape through the cell and through a corresponding color (for example, red, green, or blue) filter in the set of color filters 276 to form a color pixel in an image. When the electrode 282 is grounded, the light absorbing oil 280 returns to its previous position (as in cell 272a) and covers the aperture in the reflective aperture layer 286, absorbing any light 294 attempting to pass through it.


The roller-based light modulator 220, light tap 250, and electrowetting-based light modulation array 270 are not the only examples of MEMS light modulators suitable for inclusion in various embodiments of the invention. It will be understood that other MEMS light modulators can exist and can be usefully incorporated into the invention.


U.S. Pat. No. 7,271,945 and U.S. patent application Ser. No. 11/326,696 have described a variety of methods by which an array of shutters can be controlled via a control matrix to produce images, in many cases moving images, with appropriate gray scale. In some cases, control is accomplished by means of a passive matrix array of row and column interconnects connected to driver circuits on the periphery of the display. In other cases it is appropriate to include switching and/or data storage elements within each pixel of the array (the so-called active matrix) to improve either the speed, the gray scale and/or the power dissipation performance of the display.



FIG. 3A is a schematic diagram of a control matrix 300 suitable for controlling the light modulators incorporated into the MEMS-based display apparatus 100 of FIG. 1A, according to an illustrative embodiment of the invention. FIG. 3B is a perspective view of an array 320 of shutter-based light modulators connected to the control matrix 300 of FIG. 3A, according to an illustrative embodiment of the invention. The control matrix 300 may address an array of pixels 320 (the “array 320”). Each pixel 301 includes an elastic shutter assembly 302, such as the shutter assembly 200 of FIG. 2A, controlled by an actuator 303. Each pixel also includes an aperture layer 322 that includes apertures 324. Further electrical and mechanical descriptions of shutter assemblies such as shutter assembly 302, and variations thereon, can be found in U.S. Pat. No. 7,271,945 and U.S. patent application Ser. No. 11/326,696. Descriptions of alternate control matrices can also be found in U.S. patent application Ser. No. 11/607,715.


The control matrix 300 is fabricated as a diffused or thin-film-deposited electrical circuit on the surface of a substrate 304 on which the shutter assemblies 302 are formed. The control matrix 300 includes a scan-line interconnect 306 for each row of pixels 301 in the control matrix 300 and a data-interconnect 308 for each column of pixels 301 in the control matrix 300. Each scan-line interconnect 306 electrically connects a write-enabling voltage source 307 to the pixels 301 in a corresponding row of pixels 301. Each data interconnect 308 electrically connects a data voltage source, (“Vd source”) 309 to the pixels 301 in a corresponding column of pixels 301. In control matrix 300, the data voltage Vd provides the majority of the energy necessary for actuation of the shutter assemblies 302. Thus, the data voltage source 309 also serves as an actuation voltage source.


Referring to FIGS. 3A and 3B, for each pixel 301 or for each shutter assembly 302 in the array of pixels 320, the control matrix 300 includes a transistor 310 and a capacitor 312. The gate of each transistor 310 is electrically connected to the scan-line interconnect 306 of the row in the array 320 in which the pixel 301 is located. The source of each transistor 310 is electrically connected to its corresponding data interconnect 308. The actuators 303 of each shutter assembly 302 include two electrodes. The drain of each transistor 310 is electrically connected in parallel to one electrode of the corresponding capacitor 312 and to one of the electrodes of the corresponding actuator 303. The other electrode of the capacitor 312 and the other electrode of the actuator 303 in shutter assembly 302 are connected to a common or ground potential. In alternate implementations, the transistors 310 can be replaced with semiconductor diodes and or metal-insulator-metal sandwich type switching elements.


In operation, to form an image, the control matrix 300 write-enables each row in the array 320 in a sequence by applying Vwe to each scan-line interconnect 306 in turn. For a write-enabled row, the application of Vwe to the gates of the transistors 310 of the pixels 301 in the row allows the flow of current through the data interconnects 308 through the transistors 310 to apply a potential to the actuator 303 of the shutter assembly 302. While the row is write-enabled, data voltages Vd are selectively applied to the data interconnects 308. In implementations providing analog gray scale, the data voltage applied to each data interconnect 308 is varied in relation to the desired brightness of the pixel 301 located at the intersection of the write-enabled scan-line interconnect 306 and the data interconnect 308. In implementations providing digital control schemes, the data voltage is selected to be either a relatively low magnitude voltage (i.e., a voltage near ground) or to meet or exceed Vat (the actuation threshold voltage). In response to the application of Vat to a data interconnect 308, the actuator 303 in the corresponding shutter assembly 302 actuates, opening the shutter in that shutter assembly 302. The voltage applied to the data interconnect 308 remains stored in the capacitor 312 of the pixel 301 even after the control matrix 300 ceases to apply Vwe to a row. It is not necessary, therefore, to wait and hold the voltage Vwe on a row for times long enough for the shutter assembly 302 to actuate; such actuation can proceed after the write-enabling voltage has been removed from the row. The capacitors 312 also function as memory elements within the array 320, storing actuation instructions for periods as long as is necessary for the illumination of an image frame.


The pixels 301 as well as the control matrix 300 of the array 320 are formed on a substrate 304. The array includes an aperture layer 322, disposed on the substrate 304, which includes a set of apertures 324 for respective pixels 301 in the array 320. The apertures 324 are aligned with the shutter assemblies 302 in each pixel. In one implementation the substrate 304 is made of a transparent material, such as glass or plastic. In another implementation the substrate 304 is made of an opaque material, but in which holes are etched to form the apertures 324.


Components of shutter assemblies 302 are processed either at the same time as the control matrix 300 or in subsequent processing steps on the same substrate. The electrical components in control matrix 300 are fabricated using many thin film techniques in common with the manufacture of thin film transistor arrays for liquid crystal displays. Available techniques are described in Den Boer, Active Matrix Liquid Crystal Displays (Elsevier, Amsterdam, 2005), incorporated herein by reference. The shutter assemblies are fabricated using techniques similar to the art of micromachining or from the manufacture of micromechanical (i.e., MEMS) devices. Many applicable thin film MEMS techniques are described in Rai-Choudhury, ed., Handbook of Microlithography, Micromachining & Microfabrication (SPIE Optical Engineering Press, Bellingham, Wash. 1997), incorporated herein by reference. Fabrication techniques specific to MEMS light modulators formed on glass substrates can be found in U.S. patent application Ser. Nos. 11/361,785 and 11/731,628, incorporated herein by reference. For instance, as described in those applications, the shutter assembly 302 can be formed from thin films of amorphous silicon, deposited by a chemical vapor deposition process.


The shutter assembly 302 together with the actuator 303 can be made bi-stable. That is, the shutters can exist in at least two equilibrium positions (e.g. open or closed) with little or no power required to hold them in either position. More particularly, the shutter assembly 302 can be mechanically bi-stable. Once the shutter of the shutter assembly 302 is set in position, no electrical energy or holding voltage is required to maintain that position. The mechanical stresses on the physical elements of the shutter assembly 302 can hold the shutter in place.


The shutter assembly 302 together with the actuator 303 can also be made electrically bi-stable. In an electrically bi-stable shutter assembly, there exists a range of voltages below the actuation voltage of the shutter assembly, which if applied to a closed actuator (with the shutter being either open or closed), holds the actuator closed and the shutter in position, even if an opposing force is exerted on the shutter. The opposing force may be exerted by a spring such as spring 207 in shutter-based light modulator 200, or the opposing force may be exerted by an opposing actuator, such as an “open” or “closed” actuator.


The light modulator array 320 is depicted as having a single MEMS light modulator per pixel. Other embodiments are possible in which multiple MEMS light modulators are provided in each pixel, thereby providing the possibility of more than just binary “on” or “off” optical states in each pixel. Certain forms of coded area division gray scale are possible where multiple MEMS light modulators in the pixel are provided, and where apertures 324, which are associated with each of the light modulators, have unequal areas.


In other embodiments, the roller-based light modulator 220, the light tap 250, or the electrowetting-based light modulation array 270, as well as other MEMS-based light modulators, can be substituted for the shutter assembly 302 within the light modulator array 320.



FIGS. 4A and 4B illustrate an alternative shutter-based light modulator (shutter assembly) 400 suitable for inclusion in various embodiments of the invention. The light modulator 400 is an example of a dual actuator shutter assembly, and is shown in FIG. 4A in an open state. FIG. 4B is a view of the dual actuator shutter assembly 400 in a closed state. Shutter assembly 400 is described in further detail in U.S. patent application Ser. No. 11/251,035, referenced above. In contrast to the shutter assembly 200, shutter assembly 400 includes actuators 402 and 404 on either side of a shutter 406. Each actuator 402 and 404 is independently controlled. A first actuator, a shutter-open actuator 402, serves to open the shutter 406. A second opposing actuator, the shutter-close actuator 404, serves to close the shutter 406. Both actuators 402 and 404 are compliant beam electrode actuators. The actuators 402 and 404 open and close the shutter 406 by driving the shutter 406 substantially in a plane parallel to an aperture layer 407 over which the shutter is suspended. The shutter 406 is suspended a short distance over the aperture layer 407 by anchors 408 attached to the actuators 402 and 404. The inclusion of supports attached to both ends of the shutter 406 along its axis of movement reduces out of plane motion of the shutter 406 and confines the motion substantially a plane parallel to the substrate. By analogy to the control matrix 300 of FIG. 3A, a control matrix suitable for use with shutter assembly 400 might include one transistor and one capacitor for each of the opposing shutter-open and shutter-close actuators 402 and 404.


The shutter 406 includes two shutter apertures 412 through which light can pass. The aperture layer 407 includes a set of three apertures 409. In FIG. 4A, the shutter assembly 400 is in the open state and, as such, the shutter-open actuator 402 has been actuated, the shutter-close actuator 404 is in its relaxed position, and the centerlines of apertures 412 and 409 coincide. In FIG. 4B the shutter assembly 400 has been moved to the closed state and, as such, the shutter-open actuator 402 is in its relaxed position, the shutter-close actuator 404 has been actuated, and the light blocking portions of shutter 406 are now in position to block transmission of light through the apertures 409 (shown as dotted lines). Each aperture has at least one edge around its periphery. For example, the rectangular apertures 409 have four edges. In alternative implementations in which circular, elliptical, oval, or other curved apertures are formed in the aperture layer 407, each aperture may have only a single edge. In other implementations the apertures need not be separated or disjoint in the mathematical sense, but instead can be connected. That is to say, while portions or shaped sections of the aperture may maintain a correspondence to each shutter, several of these sections may be connected such that a single continuous perimeter of the aperture is shared by multiple shutters.


In order to allow light with a variety of exit angles to pass through apertures 412 and 409 in the open state, it is advantageous to provide a width or size for shutter apertures 412 which is larger than a corresponding width or size of apertures 409 in the aperture layer 407. In order to effectively block light from escaping in the closed state, it is preferable that the light blocking portions of the shutter 406 overlap the apertures 409. FIG. 4B shows a predefined overlap 416 between the edge of light blocking portions in the shutter 406 and one edge of the aperture 409 formed in aperture layer 407.


The electrostatic actuators 402 and 404 are designed so that their voltage—displacement behavior provides a bi-stable characteristic to the shutter assembly 400. For each of the shutter-open and shutter-close actuators there exists a range of voltages below the actuation voltage, which if applied while that actuator is in the closed state (with the shutter being either open or closed), will hold the actuator closed and the shutter in position, even after an actuation voltage is applied to the opposing actuator. The minimum voltage needed to maintain a shutter's position against such an opposing force is referred to as a maintenance voltage Vm.



FIG. 4C is a cross-sectional view of a non shutter-based MEMS light modulator 450, which includes first and second opposing actuators. The light modulator 450 is also referred to as a dual actuator light tap, which operates according to the principle of frustrated total internal reflection. The dual actuator light tap is a variation of light tap modulator 250 as described in U.S. Pat. No. 5,771,321, referred to above. The dual actuator light tap 450 comprises a light guide 454, in which, without interference, light is for the most part unable to escape through its front or rear surfaces due to total internal reflection. The light tap 450 also includes a cover sheet 452 and a flexible membrane or tap element 456. The tap element 456 has a sufficiently high index of refraction such that, in response to the tap element 456 contacting the light guide 454, light impinging on the surface of the light guide 454 adjacent the tap element 456 escapes the light guide 454 through the tap element 456 towards a viewer, thereby contributing to the formation of an image.


The tap element 456 is formed from a flexible transparent material. Electrodes 460 are coupled to the tap element 456. The light tap 450 also includes electrodes 462 and 464. The combination of electrodes 460 and 462 comprise a first actuator 470 and the combination of electrodes 460 and 464 comprise a second opposing actuator 472. By applying a voltage to the first actuator 470 the tap element 456 can be moved toward the light guide 454, allowing light to be extracted from the light guide 454. By applying a voltage to the second actuator 472 the tap element can be moved away from the light guide 454 thereby restricting the extraction of light from the light guide 454.


The actuators 470 and 472 are designed so that their voltage—displacement behavior provides an electrically bi-stable characteristic to the light tap 450. For each of the first and second actuators there exists a range of voltages below the actuation voltage, which if applied while that actuator is in the closed state, will hold the actuator closed and the tap element in position, even after an actuation voltage is applied to the opposing actuator. The minimum voltage needed to maintain the tap element's position against such an opposing force is referred to as a maintenance voltage Vm.


Electrical bi-stability arises from the fact that the electrostatic force across an actuator is a strong function of position as well as voltage. The beams of the actuators in the light modulators 400 and 450 act as capacitor plates. The force between capacitor plates is proportional to 1/d2 where d is the local separation distance between capacitor plates. In a closed actuator, the local separation between actuator beams is very small. Thus, the application of a small voltage can result in a relatively strong force between the actuator beams of a closed actuator. As a result, a relatively small voltage, such as Vm, can keep the actuator closed, even if other elements exert an opposing force on the closed actuator.


In light modulators, such as 400 and 450, that provide two opposing actuators (e.g. for the purpose of opening and closing a shutter respectively), the equilibrium position of the modulator will be determined by the combined effect of the voltage differences across each of the actuators. In other words, the electrical potentials of all three terminals (e.g. the shutter open drive beam, the shutter close drive beam, and the shutter/load beams), as well as modulator position, must be considered to determine the equilibrium forces on the modulator.


For an electrically bi-stable system, a set of logic rules can describe the stable states and can be used to develop reliable addressing or digital control schemes for the modulator. Referring to the shutter-based light modulator 400 as an example, these logic rules are as follows:


Let Vs be the electrical potential on the shutter or load beam. Let Vo be the electrical potential on the shutter-open drive beam. Let Vc be the electrical potential on the shutter-close drive beam. Let the expression /Vo−Vs/ refer to the absolute value of the voltage difference between the shutter and the shutter-open drive beam. Let Vm be the maintenance voltage. Let Vat be the actuation threshold voltage, i.e., the voltage necessary to actuate an actuator absent the application of Vm to an opposing drive beam. Let Vmax be the maximum allowable potential for Vo and Vc. Let Vm<Vat<Vmax. Then, assuming Vo and Vc remain below Vmax:

  • 1. If /Vo−Vs/<Vm and /Vc−Vs/<Vm


Then the shutter will relax to the equilibrium position of its mechanical spring.

  • 2. If /Vo−Vs/>Vm and /Vc−Vs/>Vm


Then the shutter will not move, i.e. it will hold in either the open or the closed state, whichever position was established by the last actuation event.

  • 3. If /Vo−Vs/>Vat and /Vc−Vs/<Vm


Then the shutter will move into the open position.

  • 4. If /Vo−Vs/<Vm and /Vc−Vs/>Vat


Then the shutter will move into the closed position.


Following rule 1, with voltage differences on each actuator near to zero, the shutter will relax. In many shutter assemblies the mechanically relaxed position is only partially open or closed, and so this voltage condition is preferably avoided in an addressing scheme.


The condition of rule 2 makes it possible to include a global actuation function into an addressing scheme. By maintaining a shutter voltage which provides beam voltage differences that are at least the maintenance voltage, Vm, the absolute values of the shutter open and shutter closed potentials can be altered or switched in the midst of an addressing sequence over wide voltage ranges (even where voltage differences exceed Vat) with no danger of unintentional shutter motion.


The conditions of rules 3 and 4 are those that are generally targeted during the addressing sequence to ensure the bi-stable actuation of the shutter.


The maintenance voltage difference, Vm, can be designed or expressed as a certain fraction of the actuation threshold voltage, Vat. For systems designed for a useful degree of bi-stability the maintenance voltage can exist in a range between 20% and 80% of Vat. This helps ensure that charge leakage or parasitic voltage fluctuations in the system do not result in a deviation of a set holding voltage out of its maintenance range—a deviation which could result in the unintentional actuation of a shutter. In some systems an exceptional degree of bi-stability or hysteresis can be provided, with Vm existing over a range of 2% to 98% of Vat. In these systems, however, care must be taken to ensure that an electrode voltage condition of V<Vm can be reliably obtained within the addressing and actuation time available.



FIG. 5A illustrates an alternative control matrix 500, suitable for inclusion in the display apparatus 100, according to an illustrative embodiment of the invention. Control matrix 500 controls an array of pixels 504 that include dual-actuator shutter assemblies 512. Dual actuator shutter assemblies, such as shutter assembly 400, are shutter assemblies that include separate shutter-open and shutter-close actuators. Although only one pixel 504 is illustrated in FIG. 5A, it is understood that the control matrix extends and incorporates a large number of rows and columns of similar pixels, as is partially illustrated by the control matrix 300 of FIG. 3A. In addition, the control matrix may be used with any suitable type of MEMS modulators and actuators, such as elastic modulators, single-actuator modulators, non-shutter based modulators, and modulators 200, 220, 250, 270, 400 and 450 without departing from the scope of the invention. The control matrix 500 includes column line interconnect 502 for each column of pixels 504 in the control matrix. The actuators in the shutter assemblies 504 can be made either electrically bi-stable or mechanically bi-stable. The light control matrix 500 is depicted as having a single MEMS light modulator per pixel. Other embodiments are possible in which multiple MEMS light modulators are provided in each pixel, thereby providing the possibility of more than just binary “on” or “off” optical states in each pixel. Certain forms of coded area division gray scale are possible where multiple MEMS light modulators in the pixel are provided, and where apertures, which are associated with each of the light modulators, have unequal areas.


The control matrix 500 includes a plurality of lines, herein referred to as “global lines” common to the entire display, composed of a plurality of identical pixels arranged in a row and column fashion. These global lines include the actuate line interconnect 506 the common line interconnect 518, the shutter line interconnect 520, and the update line interconnect 522 In some embodiments these global lines are operated as one node across the entire display. For example, the entire update node across the display, or the entire actuate node across the display is changed at the same time. In some embodiments, these global line interconnects can be grouped into pixel sub-groups. For example, each odd row of pixels may have their global lines connected, and each even row of pixels' global lines may be separately connected so that odd rows may be operated independently of even rows. The control matrix 500 includes a row line, 524, unique to each row arrangement of pixels and a column line, 502, unique to each column arrangement of pixels. Each pixel 504 in the control matrix includes a data loading transistor 534, a data store capacitor 538, an update transistor 536, actuator nodes 540 and 542, and a dual inverter latch. In control matrix 500, the data store capacitor 538 is connected to the common line interconnect 518. However, in some embodiments the data store capacitor 538 may be connected to the shutter line interconnect 520. In some embodiments, the common line interconnect 518 can serve as the next row's row interconnect 524, and therefore eliminating the common line interconnect 518 altogether.


The dual inverter latch includes a first inverter comprised of transistors 526 and 530, and a second inverter comprised of transistors 528 and 532. Shutter assemblies 512 include electrostatic actuators, similar to actuator 204 of shutter assembly 200, connected to the actuator nodes 540 and 542. When a voltage difference equal to or greater than an actuation voltage, also referred to as a charging voltage or Vat, is imposed between the actuators and the shutter, the shutter assembly can be driven into an open state allowing passage of light, or a closed state, blocking the passage of light. The control matrix 500 makes use of two complementary types of transistors: both p-channel and n-channel transistors. It is therefore referred to as a complementary MOS control matrix or a CMOS control matrix. While the data loading transistor 534, update transistor 536 and the lower transistors of the cross-coupled inverters 530 and 532 are made of the nMOS type, the upper transistors of the cross-coupled inverter 526 and 528 are made of the pMOS type of transistor. Those of skill in the art will recognize that in other implementations, the types of CMOS transistors can be reversed (i.e., pMOS switched with nMOS), or other types of transistors may be used (i.e., BJT, JFET or any other suitable type of transistor).


In some embodiments, actuate line 506 is connected to a voltage source that is maintained equal to or greater than Vat. The shutter line 520 is maintained near to the ground potential. In some embodiments, the shutter polarity may be maintained at the full actuation voltage (i.e., approximately 25 volts). In certain embodiments, the polarity of the shutter may be periodically alternated between one or more potentials as necessary. For example, the shutter may be alternated between 25 volts and 0 volts after each full video frame, or in other cases, more or less frequently. The shutter polarity may be controlled by applying the necessary voltage to the shutter line interconnect 520. In some embodiments, the polarity of the data is alternated, as well, corresponding to the shutter potential being alternated.


Each actuator node 540 and 542 is connected to actuate line 506 depending on the “on/off” state of its respective transistor 526 and 528. For example, when the transistor 526 connected to the left actuator node 540 is in an “on” state, charge is allowed to flow from the actuate line 506 to the actuator node 540. Then, a voltage of approximately Vat will be imposed between the actuator connected to the actuator node 540 and the shutter (assuming the shutter is at common potential), and the shutter will be driven into its desired state. A similar process occurs when transistor 526 is in an “off” state and transistor 528 is in an “on” state, which results in driving the shutter into the opposite state. In some embodiments, a voltage of approximately Vat will be applied to the actuator connected to the actuator node 540 and a similar voltage applied to the shutter, thereby creating a 0 volt potential between the shutter and actuator.


The control matrix 500 includes a data store capacitor 538. As described further below, the capacitor 538 stores, by means of stored charge, “data” instructions (e.g., open or close) that are sent by a controller, such as controller 156, to the pixel 504 as part of a data loading or writing operation. The voltage stored on the capacitor 538 determines, in part, the latch state of the dual inverter latch in control matrix 500.


During a data load operation, each row of the array is write-enabled in an addressing sequence. The voltage sources in control matrix 500 (not shown) apply a write-enabling voltage to the row line interconnect 524 corresponding to a selected row. The application of voltage to the row line interconnect 524 for the write-enabled row turns on the data-loading transistor 534 of the pixels 504 in the corresponding row line, thereby write enabling the pixels. While a selected row of pixels 504 is write-enabled, data voltage sources apply appropriate data voltages to the column interconnect 502 corresponding to each column of pixels 504 in the control matrix 500. The voltages applied to the column interconnects 502 are thereby stored on the data store capacitors 538 of the respective pixels 504. In certain embodiments, the voltages applied to column interconnect 502 may be negative or positive (e.g., ranging from −5 to 5 volts).


A method of addressing pixels in control matrix 500 is illustrated by the method 550 shown in FIG. 5B. The method 550 proceeds in three general steps. First, data is loaded row by row to each pixel in the data loading step 552. Next, the latch for each pixel is set to the correct state based, at least in part, on the stored data in the update latch state step 554. Finally, the shutters are actuated in the shutter actuation step 556.


In more detail, the frame addressing cycle of method 550 begins in a held data state with the actuate line 506 at the full voltage Vat needed to reliably actuate the shutter to the appropriate actuator node (Step 558). For example this voltage may be approximately 20-30 volts. The control matrix 500 then proceeds with the data loading step 552 by addressing each pixel 504 in the control matrix, one row at a time (steps 556-570). To address a particular row, the control matrix 500 write-enables a first row line by applying a voltage to the corresponding row-line interconnect 524 (step 566), effectively switching the data loading transistor 534 to a conductive “on” state. Then, at decision block 560, the control matrix 500 determines for each pixel 504 in the write-enabled row whether the pixel 504 needs to be open or closed in the next state. For example, at step 560 it is determined for each pixel 504 in the write-enabled row whether or not the pixel is to be (subsequently) changed from its current state or kept the same. If a pixel 504 is to be opened, the control matrix 500 loads a particular data voltage Vd, for example 1.5V, to the column interconnect 502 corresponding to the column in which that pixel 504 is located (step 562). If a pixel 504 is to be closed, the control matrix 500 loads a particular data voltage Vd, for example −1.5V, to the column interconnect 502 corresponding to the column in which that pixel 504 is located (step 564). The data voltage Vd applied to the column interconnect 502, corresponding to the next state of the shutter, is then stored by means of a charge on the data store capacitor 538 of the selected pixel 504 (step 568). Next, the voltage is removed from the row line 524 (step 570), effectively switching the data loading transistor 534 to a non-conducting “off” state. Once data loading transistor 534 is set to the “off” state, column line 502 is ready to load the data voltage Vd for the next state.


The data voltage Vd can be set at any time as long as it is valid when the row line 524 is turned off, so that the correct data is on the data storage capacitor 538 when data loading transistor 534 becomes non conductive. During the data loading step 552, the update line 522 is inactive, thereby isolating the data storage capacitor 538 from the current state held by the transistors 526-532 of the cross-coupled inverter latch.


After all data for the next state has been stored on capacitors 538 in the selected rows in data loading step 552 (steps 566-570), the control matrix 500 then proceeds with the update latch step 554 to update portions or banks of the pixels, or the entire display to the next held state. The update latch sequence begins at step 572 of method 550 by bringing the voltage on the actuate line 506 down, or close, to the voltage on the common line 518. This brings the voltages on both the actuator nodes 540 and 542 close to the same voltage as the common line 518. Next, the update line 522 is activated in step 574, thereby switching the update transistor 536 to a conductive “on” state and allowing the stored data to be passed from the data store capacitor 538 to the transistors 526-532 of the cross-coupled inverter latch. If the update line 522 is activated (step 574) too early after the actuate line 506 voltage is brought to the common line 518 voltage (step 572), the stored next state of the next state data can be corrupted by present state data of the latch that has not had enough time to decay away. This necessary non-overlap timing can be a function of circuit parasitics, transistor threshold voltages, capacitor size and stored data voltage levels. For example, the delay needed between steps 572 and 574 may be approximately 10 μs, however this delay time may be considerably longer or shorter depending on the display.


An intermediate voltage just high enough to make the latch transistors operate (e.g. approximately equal to the sum of the threshold voltages of the inverter transistors 526 and 530 or 528 and 532. The level can be significantly less, limited by the details of needed timings, parasitic charge injections, detailed transistor characteristics, and the like.) is applied to the actuate line 506 in step 576. The intermediate voltage applied to the actuate line 506 in step 576 functions to minimize the power used to latch to the next state. In certain embodiments, the cross-coupled inverter latch is latched at as low an intermediate voltage level as can be reliably performed in order to reduce overall transient switching power. Steps 574 and 576 cause the data stored on data store capacitor 538 to be latched in the cross-coupled inverter latch of pixel 504.


Step 576 may be performed simultaneously to, before or after activating the update line 522 in step 574. For example, in certain embodiments, applying an intermediate voltage to the actuate line 506 in step 576 can be done completely after the update pulse created in steps 574 and 578 or the intermediate voltage pulse created in step 576 can partially or fully overlap with the update voltage pulse. In some embodiments, control of the next state of the cross-coupled inverter latch is executed by overlap of the two states, particularly if parasitic capacitances of the data latch are low.


Finally, the update line 522 is inactivated in step 578, thereby switching the update transistor 536 to a non-conductive “off” state and isolating the data store capacitor 538 from the cross-coupled inverter latch of pixel 504. By inactivating the update line 522 (step 578) before raising the actuate line to full voltage (step 580) significant power is conserved by not allowing the data storage capacitor 538 to be charged to the full actuation voltage.


On the other hand, it is possible to not have the update transistor, 536, at all. In this case the data loading operation would directly change the latch state as it is loaded row by row. This could happen by simultaneously lowering the actuate node to the appropriate intermediate level or to approximately 0 then to the intermediate level on a row by row basis as well to allow for lower data voltages to determine the latch state, or by lowering the actuate node for the entire display to an appropriate intermediate level during the entire data loading operation, or, if power is not a concern, or the actuation voltages are low enough to make the power a secondary concern, the data voltages could be at full actuation voltage levels, or more, with the actuate node maintained at the full Vac, to force the latch to the desired state. Also, by eliminating update transistor 536, layout area may be saved.


Once the data has been transferred and the latch state updated in step 554, the control matrix 500 proceeds with the shutter actuation step 556 to move the shutters, of shutter assemblies 512, to their next state. Shutter actuation step 556 includes raising the actuate line 506 to full voltage in step 580. Full voltage may be the voltage necessary to actuate the shutter to one side or the other and to hold the shutter in that position until the next frame addressing cycle. Because the latch state was set earlier during the update latch state step 554, there is no conduction path from the actuate line 506 through the two transistors in series in each inverter (526 and 530 or 528 and 532). Thus, only current meant to charge the actuation of the shutter capacitance and various parasitic capacitance is allowed to flow, resulting in minimal power dissipation. After the shutters are actuated in step 556, method 550 returns to the beginning of the pixel addressing cycle.


The action of the cross coupled inverter latch in control matrix 500 requires only one shutter transition time to get to its next state. Previous methods of display control require two shutter transition times to fully update the entire display. This difference of time for the extra shutter transition can be significant for more complicated display algorithms where many display updates are done in one video frame time. Additionally, control matrix 500 creates a held data state where only one actuator is attractive to the shutter and the other actuator is not attractive. This helps to prevent erroneous shutter states.


In certain embodiments, it is possible to approximate the dual voltage level actuate operation to reduce latching transients in the cross-coupled inverter latch by slewing the actuate line 506 voltage slow enough that the latching operation of the cross coupled inverter latch happens at a low voltage, thus saving power. The timing of the update signal relative to the actuate node voltage level allows for control of excessive charging of the data storage capacitor 538 to assure lower power operation.



FIG. 6 is another suitable control matrix 600 for inclusion in the display apparatus 100, according to an illustrative embodiment of the invention. Similarly to control matrix 500, control matrix 600 controls an array of pixels that include dual-actuator shutter assemblies 612. However, any type of MEMS shutter and actuators assembly may be used without departing from the scope of the invention.


The control matrix 600 also includes a plurality of global lines common to the entire display, composed of a plurality of identical pixels arranged in a row and column fashion. These global lines include the actuate line interconnect 606 the common line interconnect 618, the shutter line interconnect 620, and the update line interconnect 622 In some embodiments these global lines are operated as one node across the entire display. For example, the entire update node across the display, or the entire actuate node across the display is changed at the same time. In some embodiments, these global line interconnects can be grouped into pixel sub-groups. For example, each odd row of pixels may have their global lines connected, and each even row of pixels' global lines may be separately connected so that odd rows may be operated independently of even rows. The control matrix 600 includes a row line, 624, unique to each row arrangement of pixels and a column line, 602, unique to each column arrangement of pixels. Each pixel 604 in the control matrix 600 includes a data loading transistor 634, a data store capacitor 638, an update transistor 636, and a dual inverter latch. The dual inverter latch of control matrix 600 includes a first inverter with dual gate transistors including transistors 626, 644, 646 and 630 connected in series, and a second inverter with dual gate transistors including transistors 628, 640, 642 and 632 connected in series.


Control matrix 600 operates in a similar manner to control matrix 500 and as described in method 550. However, control matrix 600 includes four added transistors forming dual gate transistors in the cross-coupled inverters of pixel 604. The dual gate transistors of control matrix 600 are connected in series and have a common gate potential. This allows for operation of control matrix 600 at higher actuation voltages. For example, many thin film transistors are rated to withstand approximately 15 volts. The dual gate transistors of control matrix 600 operate to partially share the voltage stress and allow for the application of higher actuation voltages (i.e. 15-30 volts) to the shutter actuators. The dual gate transistor design of matrix 600 does not require an added interconnect.



FIG. 7 is another suitable control matrix 700 for inclusion in the display apparatus 100, according to an illustrative embodiment of the invention. Similarly to control matrix 500, control matrix 700 controls an array of pixels that include dual-actuator shutter assemblies 712. However, any type of MEMS shutter and actuators assembly may be used without departing from the scope of the invention.


The control matrix 700 also includes a plurality of global lines common to the entire display, composed of a plurality of identical pixels arranged in a row and column fashion. These global lines include the actuate line interconnect 706 the common line interconnect 718, the shutter line interconnect 720, and the update line interconnect 722 In some embodiments these global lines are operated as one node across the entire display. For example, the entire update node across the display, or the entire actuate node across the display is changed at the same time. In some embodiments, these global line interconnects can be grouped into pixel sub-groups. For example, each odd row of pixels may have their global lines connected, and each even row of pixels' global lines may be separately connected so that odd rows may be operated independently of even rows. The control matrix 700 includes a row line, 724, unique to each row arrangement of pixels and a column line, 702, unique to each column arrangement of pixels. Each pixel 704 in the control matrix 700 includes a data loading transistor 734, a data store capacitor 738, an update transistor 736, and a dual inverter latch. The dual inverter latch of control matrix 700 includes a first inverter including transistors 726, 744, 746 and 730 connected in series and cascode 750 connected to the gates of cascode transistors 744 and 746, and a second inverter including transistors 728, 740, 742 and 732 connected in series and cascode 748 is connected to the gates of cascode transistors 740 and 742. In practice cascodes 748 and 750 are connected to the same cascode node, however, this is not shown in FIG. 7 for purposes of clarity.


Control matrix 700 operates in a similar manner to control matrix 500 and as described in method 550. However, control matrix 700 includes four added transistors and a cascode node 748 connected to the cross-coupled inverters of pixel 604. The cascodes of control matrix 700 operate to keep all transistors in the cross-coupled inverter at an approximate maximum of ½ the voltage on the actuate line 706, and allow the cascode transistors 744 and 746, and 740 and 742 to act as shields for excessive voltage on the other transistors in the inverters (726, 730 and 728, 732). The cascode node is pulsed with the actuate line 706 voltage at all times (i.e., both during the update sequence as well as during the held data state). For example, the cascode node may be pulsed in such a way that it follows the actuate node at approximately ½ its potential. This allows for operation of control matrix 700 at actuation voltages even higher than that of control matrix 600. The use of cascodes are explained in more detail in U.S. patent application Ser. No. 11/811,842, which is incorporated herein by reference.



FIG. 8 is another suitable control matrix 800 for inclusion in the display apparatus 100, according to an illustrative embodiment of the invention. Similarly to control matrix 500, control matrix 800 controls an array of pixels that include dual-actuator shutter assemblies 812. However, any type of MEMS shutter and actuators assembly may be used without departing from the scope of the invention.


The control matrix 800 also includes a plurality of global lines common to the entire display, composed of a plurality of identical pixels arranged in a row and column fashion. These global lines include the actuate line interconnect 806 the common line interconnect 818, the shutter line interconnect 820, and the update line interconnect 822. In some embodiments these global lines are operated as one node across the entire display. For example, the entire update node across the display, or the entire actuate node across the display is changed at the same time. In some embodiments, these global line interconnects can be grouped into pixel sub-groups. For example, each odd row of pixels may have their global lines connected, and each even row of pixels' global lines may be separately connected so that odd rows may be operated independently of even rows. The control matrix 800 includes a row line, 824, unique to each row arrangement of pixels and a column line, 802, unique to each column arrangement of pixels. Each pixel 804 in the control matrix 800 includes a data loading transistor 834, a data store capacitor 838, an update transistor 836, and a dual inverter latch. The dual inverter latch of control matrix 800 includes a first inverter including transistors 826 and 830, and a second inverter including transistors 828 and 832.


Control matrix 800 operates in a similar manner to control matrix 500 and as described in method 550. However, the transistors 826-836 control matrix 800 are flipped with respect to the control matrix 500 (i.e, pMOS to nMOS and vise versa). It is known by those of skill in the art that the transistors of control matrices 600 and 700 may be flipped in a similar manner. In control matrix 800, the data loading transistor 834, update transistor 836 and the two bottom transistors of the cross-coupled inverter 830 and 832 are pMOS, while the two upper transistors on the cross-coupled inverter 826 and 828 are nMOS. The control matrix 800 functions in a similar manner to that of control matrix 500 and as described in method 550, however the polarities of the voltages may be reversed.



FIG. 9A is a chart 900 of voltage variations vs. time during pixel operation using control matrix 500, according to an illustrative embodiment of the invention. For example, chart 900 may be the voltage variations resulting from applying method 550 to the control matrix 500. Plot 902 represents the voltage variation vs. time on actuator node 540. Plot 904 represents the voltage variation vs. time on update line 522. Plot 906 represents the voltage variation vs. time on data store capacitor 538. Plot 908 represents the voltage variation vs. time on the opposite actuator node 542. Reference numbers 910-922 represent events corresponding to method 550.


Starting at event 910, the voltage 902 on actuator node 540 is at full voltage (approximately 25 volts). This corresponds to the actuate line 506 being at full voltage in step 558 of method 550. During this phase, the shutter is held attractive to actuator node 540 in its current state. At event 912, the next state data is stored in the data store capacitor 538 corresponding to step 568 of method 550. The voltage 906 on the data store capacitor 538 increases at event 912 to reflect the stored data. Next, at event 914, the actuate line 506 voltage is brought to common line 518 voltage corresponding to step 572 of method 550. After event 914, the voltage 902 on actuator node 540 decreases dramatically. At event 916, the update line 522 is activated, corresponding to step 574 of method 550. When the update line is activated, the voltage 904 on the update line increases to approximately 12 volts for a very short period of time until update line 522 is inactivated at event 918, corresponding to step 578 of method 550. Also, at event 918, an intermediate voltage is applied to actuate line 506, corresponding to step 576 of method 550, to set the latch state on the cross-coupled inverters. As described above, in certain embodiments, the intermediate voltage may be applied to actuate line 506 before, during or after event 918 when the update line 522 is inactivated. As shown in chart 900, the intermediate voltage 908 applied to the actuate line 506 may be approximately 7 volts. Finally, at event 920, the actuate line 506 is raised to full voltage, corresponding to step 580 of method 550, causing the voltage on the opposite actuator node 542 to increase to approximately 25 volts. During this phase, the shutter is attracted to actuator node 542 and is held there until the next frame addressing cycle. At event 922, data is stored on the data store capacitor 538 for the next state in the frame addressing cycle.



FIG. 9B is a chart 950 showing the transition detail of the voltage variations vs. time from chart 900, according to an illustrative embodiment of the invention. Chart 950 shows a close-up of the voltage transitions adjacent and during the activation of the update line at event 916. Chart 950 further includes plot 924 representing the voltage variation vs. time on actuate line 506. As illustrated in chart 950, the voltage in plot 924 starts to increase toward an intermediate level after event 916 when the update line 522 is activated (step 574), and slightly before event 918, when the update line 522 is inactivated (step 578).



FIG. 10A is a chart 1000 of the voltage increase on the actuate node during pixel operation, according to an illustrative embodiment of the invention. Specifically, chart 1000 shows the voltage increase on actuate node during step 576 of method 550 as the voltage on the actuate line 506 is ramped up to an intermediate voltage (i.e. approximately 7 volts). FIG. 10B is a chart 1050 of the latch current transient of the coupled transistors during the voltage ramp-up of chart 1000, according to an illustrative embodiment of the invention. Specifically, chart 1050 shows the current from the power supply that provides power to the actuate line 506. Chart 1050 shows that only approximately 650 fCoulombs of charge flow when applying an intermediate voltage to the actuate line (step 576).



FIG. 11A is a chart 1100 of the voltage increase on an actuator node during pixel operation, according to another illustrative embodiment of the invention. Specifically, chart 1100 shows the voltage increase on the actuate node during step 576 of method 550 as the voltage on the actuate line 506 is ramped up to full voltage (i.e. approximately 25 volts). FIG. 11B is a chart 1150 of the latch current transient of the coupled transistors during the voltage ramp-up of chart 1100, according to an illustrative embodiment of the invention. Specifically, chart 1150 shows the current from the power supply that provides power to the actuate line 506. Chart 1150 shows that approximately 8000 fCoulombs of charge flow when applying the full voltage to the actuate line (step 576), considerably more than that shown in chart 1050 when an intermediate voltage is applied to the actuate line 506. Thus, the intermediate voltage stage applied in step 576 of method 550 provides considerable amount of power savings, while still causing the cross-coupled inverters to latch in the correct state.


The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The forgoing embodiments are therefore to be considered in all respects illustrative, rather than limiting of the invention.

Claims
  • 1. A method for addressing pixels in a display wherein each pixel includes a MEMS-based light modulator, first and second actuators, and a separate dual inverter latch electrically coupling the first and second actuators for maintaining an opposite logical state on the first and second actuators comprising: loading data into a data store coupled to the dual inverter latch, wherein loading data into the data store comprises: applying a write-enable voltage to a row interconnect associated with a row in the display;determining the next state of at least one pixel in the row; andapplying a data voltage corresponding to the next state of the pixel to a corresponding column interconnect;updating the latch state based at least in part on the loaded data such that a full actuation voltage is only applied to one of the first and second actuators; andactuating the MEMS-based light modulator.
  • 2. The method of claim 1, wherein actuating the MEMS-based light modulator comprises applying voltages to the MEMS-based light modulator and the first and second actuators in accordance with a polarity reversal process.
  • 3. The method of claim 1, wherein the data store comprises a capacitor and the method further comprises storing the applied data voltage as electrical charge on the capacitor.
  • 4. The method of claim 1, wherein the display further comprises an actuate interconnect coupled to the dual inverter latch and a common interconnect coupled to the dual inverter latch, and wherein updating the latch state further comprises: setting the actuate interconnect voltage to be approximately the same as the common interconnect voltage;applying an update voltage to an update interconnect;applying an intermediate voltage to the actuate interconnect; andremoving the update voltage from the update interconnect.
  • 5. The method of claim 4, wherein applying an update voltage to the update interconnect further comprises: switching at least one update switch connected to the update interconnect to an ‘on’ state; andallowing stored data to be passed from the data store to the dual inverter latch.
  • 6. The method of claim 5, wherein removing the update voltage from the update interconnect further comprises electrically isolating the data store from the dual inverter latch.
  • 7. The method of claim 4, wherein removing the update voltage from the update interconnect occurs prior to actuating the MEMS-based light modulator.
  • 8. The method of claim 4, wherein setting the actuate interconnect voltage to be approximately the same as the common interconnect voltage occurs prior to applying an update voltage to the update interconnect, and wherein there is a delay between setting the actuation interconnect voltage and applying an update voltage.
  • 9. The method of claim 4, wherein applying an intermediate voltage to the actuate interconnect occurs before applying an update voltage to the update interconnect.
  • 10. The method of claim 4, wherein applying an intermediate voltage to the actuate interconnect occurs after applying an update voltage to the update interconnect.
  • 11. The method of claim 4, wherein applying an intermediate voltage to the actuate interconnect occurs simultaneously with applying an update voltage to the update interconnect.
  • 12. The method of claim 4, wherein the intermediate voltage is selected to be sufficient to latch the dual inverter latch corresponding to the data stored in the data store.
  • 13. The method of claim 4, wherein the common interconnect is held at ground potential.
  • 14. The method of claim 4, wherein actuating the MEMS-based light modulator comprises raising the voltage on the actuate interconnect to full voltage.
  • 15. The method of claim 14, wherein the full voltage is the voltage necessary to actuate and hold the MEMS-based light modulator in a logical state.
  • 16. The method of claim 15, wherein actuating the MEMS-based light modulator includes causing the light modulator to be attractive to only one of the first and second actuators.
US Referenced Citations (820)
Number Name Date Kind
3864582 Keeler Feb 1975 A
4067043 Perry Jan 1978 A
4074253 Nadir Feb 1978 A
4421381 Ueda et al. Dec 1983 A
4559535 Watkins et al. Dec 1985 A
4563836 Woodruff et al. Jan 1986 A
4564836 Vuilleumier et al. Jan 1986 A
4582396 Bos et al. Apr 1986 A
4673253 Tanabe et al. Jun 1987 A
4728936 Guscott et al. Mar 1988 A
4744640 Phillips May 1988 A
4889603 DiSanto et al. Dec 1989 A
4958911 Beiswenger et al. Sep 1990 A
4991941 Kalmanash Feb 1991 A
5005108 Pristash et al. Apr 1991 A
5025346 Tang et al. Jun 1991 A
5025356 Gawad Jun 1991 A
5042900 Parker Aug 1991 A
5044734 Sperl et al. Sep 1991 A
5050946 Hathaway et al. Sep 1991 A
5061049 Hornbeck Oct 1991 A
5062689 Koehler Nov 1991 A
5078479 Vuilleumier Jan 1992 A
5093652 Bull et al. Mar 1992 A
5096279 Hornbeck et al. Mar 1992 A
5128787 Blonder Jul 1992 A
5136480 Pristash et al. Aug 1992 A
5136751 Coyne et al. Aug 1992 A
5142405 Hornbeck Aug 1992 A
5184248 De Vaan et al. Feb 1993 A
5184428 Feldt et al. Feb 1993 A
5198730 Vancil Mar 1993 A
5202950 Arego et al. Apr 1993 A
5233385 Sampsell Aug 1993 A
5233459 Bozler et al. Aug 1993 A
5245454 Blonder Sep 1993 A
5266612 Kim et al. Nov 1993 A
5278652 Urbanus et al. Jan 1994 A
5280277 Hornbeck Jan 1994 A
5319061 Ramaswamy Jun 1994 A
5319491 Selbrede Jun 1994 A
5339116 Urbanus et al. Aug 1994 A
5339179 Rudisill et al. Aug 1994 A
5359345 Hunter Oct 1994 A
5379135 Nakagaki et al. Jan 1995 A
5393710 Park et al. Feb 1995 A
5396350 Beeson et al. Mar 1995 A
5405490 Park et al. Apr 1995 A
5416631 Yagi May 1995 A
5440197 Gleckman Aug 1995 A
5452024 Sampsell Sep 1995 A
5461411 Florence et al. Oct 1995 A
5465175 Woodgate et al. Nov 1995 A
5467104 Furness, III Nov 1995 A
5477086 Rostoker et al. Dec 1995 A
5479279 Barbier et al. Dec 1995 A
5491347 Allen et al. Feb 1996 A
5493439 Engle Feb 1996 A
5497172 Doherty et al. Mar 1996 A
5497258 Ju et al. Mar 1996 A
5499127 Tsubota et al. Mar 1996 A
5504389 Dickey Apr 1996 A
5504614 Webb et al. Apr 1996 A
5510824 Nelson Apr 1996 A
5517341 Kim et al. May 1996 A
5517347 Sampsell May 1996 A
5519240 Suzuki May 1996 A
5519565 Kalt et al. May 1996 A
5523803 Urbanus et al. Jun 1996 A
5526051 Gove et al. Jun 1996 A
5528262 McDowall et al. Jun 1996 A
5548301 Kornher et al. Aug 1996 A
5548670 Koike Aug 1996 A
5552925 Worley Sep 1996 A
5559389 Spindt et al. Sep 1996 A
5568964 Parker et al. Oct 1996 A
5578185 Bergeron et al. Nov 1996 A
5579035 Beiswenger Nov 1996 A
5579240 Buus Nov 1996 A
5591049 Dohnishi Jan 1997 A
5596339 Furness, III Jan 1997 A
5596369 Chau Jan 1997 A
5613751 Parker et al. Mar 1997 A
5618096 Parker et al. Apr 1997 A
5619266 Tomita et al. Apr 1997 A
5622612 Mihara et al. Apr 1997 A
5629784 Abileah et al. May 1997 A
5629787 Tsubota et al. May 1997 A
5655832 Pelka et al. Aug 1997 A
5655838 Ridley et al. Aug 1997 A
5659327 Furness, III Aug 1997 A
5663917 Oka et al. Sep 1997 A
5666226 Ezra et al. Sep 1997 A
5677749 Tsubota et al. Oct 1997 A
5684354 Gleckman Nov 1997 A
5687465 Hinata et al. Nov 1997 A
5691695 Lahiff Nov 1997 A
5694227 Starkweather Dec 1997 A
5724062 Hunter Mar 1998 A
5731802 Aras et al. Mar 1998 A
5745193 Urbanus et al. Apr 1998 A
5745203 Valliath et al. Apr 1998 A
5745281 Yi et al. Apr 1998 A
5745284 Goldberg et al. Apr 1998 A
5771321 Stern Jun 1998 A
5781331 Carr et al. Jul 1998 A
5781333 Lanzillotta et al. Jul 1998 A
5784189 Bozler et al. Jul 1998 A
5794761 Renaud et al. Aug 1998 A
5798746 Koyama Aug 1998 A
5801792 Smith et al. Sep 1998 A
5808800 Handschy et al. Sep 1998 A
5810469 Weinreich Sep 1998 A
5815134 Nishi Sep 1998 A
5835255 Miles Nov 1998 A
5835256 Huibers Nov 1998 A
5854872 Tai Dec 1998 A
5867302 Fleming Feb 1999 A
5876107 Parker et al. Mar 1999 A
5884872 Greenhalgh Mar 1999 A
5889625 Chen et al. Mar 1999 A
5894686 Parker et al. Apr 1999 A
5895115 Parker et al. Apr 1999 A
5917692 Schmitz et al. Jun 1999 A
5921652 Parker et al. Jul 1999 A
5923480 Labeye Jul 1999 A
5926591 Labeye et al. Jul 1999 A
5936596 Yoshida et al. Aug 1999 A
5943223 Pond Aug 1999 A
5953469 Zhou Sep 1999 A
5959763 Bozler et al. Sep 1999 A
5963367 Aksyuk et al. Oct 1999 A
5973727 McGrew et al. Oct 1999 A
5975711 Parker et al. Nov 1999 A
5986628 Tuenge et al. Nov 1999 A
5986796 Miles Nov 1999 A
5986828 Wood et al. Nov 1999 A
5990990 Crabtree Nov 1999 A
5994204 Young et al. Nov 1999 A
5995688 Aksyuk et al. Nov 1999 A
6008781 Furness, III Dec 1999 A
6008929 Akimoto et al. Dec 1999 A
6028656 Buhrer et al. Feb 2000 A
6030089 Parker et al. Feb 2000 A
6034807 Little et al. Mar 2000 A
6040796 Matsugatani et al. Mar 2000 A
6040937 Miles Mar 2000 A
6046840 Huibers Apr 2000 A
6049317 Thompson et al. Apr 2000 A
6055090 Miles Apr 2000 A
6069676 Yuyama May 2000 A
6079838 Parker et al. Jun 2000 A
6111560 May Aug 2000 A
6130527 Bontempo et al. Oct 2000 A
6130735 Hatanaka et al. Oct 2000 A
6137313 Wong et al. Oct 2000 A
6154586 MacDonald et al. Nov 2000 A
6158867 Parker et al. Dec 2000 A
6162657 Schiele et al. Dec 2000 A
6168395 Quenzer et al. Jan 2001 B1
6172657 Kamakura et al. Jan 2001 B1
6172797 Huibers Jan 2001 B1
6174064 Kalantar et al. Jan 2001 B1
6195196 Kimura et al. Feb 2001 B1
6201633 Peeters et al. Mar 2001 B1
6201664 Le et al. Mar 2001 B1
6206550 Fukushima et al. Mar 2001 B1
6215536 Ebihara et al. Apr 2001 B1
6219119 Nakai Apr 2001 B1
6225991 McKnight May 2001 B1
6227677 Willis May 2001 B1
6239777 Sugahara et al. May 2001 B1
6249169 Okada Jun 2001 B1
6249269 Blalock et al. Jun 2001 B1
6249370 Takeuchi et al. Jun 2001 B1
6266240 Urban et al. Jul 2001 B1
6275320 Dhuler et al. Aug 2001 B1
6282951 Loga et al. Sep 2001 B1
6285270 Lane et al. Sep 2001 B1
6288824 Kastalsky Sep 2001 B1
6288829 Kimura Sep 2001 B1
6295054 McKnight Sep 2001 B1
6296383 Henningsen Oct 2001 B1
6296838 Bindra et al. Oct 2001 B1
6300154 Clark et al. Oct 2001 B2
6300294 Robbins et al. Oct 2001 B1
6317103 Furness, III Nov 2001 B1
6323834 Colgan et al. Nov 2001 B1
6329967 Little et al. Dec 2001 B1
6329971 McKnight Dec 2001 B2
6329974 Walker Dec 2001 B1
6360033 Lee et al. Mar 2002 B1
6367940 Parker et al. Apr 2002 B1
6388661 Richards May 2002 B1
6392736 Furukawa et al. May 2002 B1
6402335 Kalantar et al. Jun 2002 B1
6402355 Kinouchi Jun 2002 B1
6404942 Edwards et al. Jun 2002 B1
6407851 Islam et al. Jun 2002 B1
6411423 Ham Jun 2002 B2
6424329 Okita Jul 2002 B1
6424388 Colgan et al. Jul 2002 B1
6428173 Dhuler et al. Aug 2002 B1
6429625 LeFevre et al. Aug 2002 B1
6429628 Nakagawa Aug 2002 B2
6459467 Hashimoto et al. Oct 2002 B1
6471879 Hanson et al. Oct 2002 B2
6473220 Clikeman et al. Oct 2002 B1
6476886 Krusius et al. Nov 2002 B2
6483613 Woodgate et al. Nov 2002 B1
6486997 Bruzzone et al. Nov 2002 B1
6498685 Johnson Dec 2002 B1
6504985 Parker et al. Jan 2003 B2
6507138 Rodgers et al. Jan 2003 B1
6508563 Parker et al. Jan 2003 B2
6514111 Ebihara et al. Feb 2003 B2
6523961 Ilkov et al. Feb 2003 B2
6529250 Murakami et al. Mar 2003 B1
6529265 Henningsen Mar 2003 B1
6531329 Asakura et al. Mar 2003 B2
6531947 Weaver et al. Mar 2003 B1
6532044 Conner et al. Mar 2003 B1
6535256 Ishihara et al. Mar 2003 B1
6535311 Lindquist Mar 2003 B1
6556258 Yoshida et al. Apr 2003 B1
6556261 Krusius et al. Apr 2003 B1
6559827 Mangerson May 2003 B1
6567063 Okita May 2003 B1
6567138 Krusius et al. May 2003 B1
6574033 Chui et al. Jun 2003 B1
6576887 Whitney et al. Jun 2003 B2
6582095 Toyoda Jun 2003 B1
6583915 Hong et al. Jun 2003 B1
6589625 Kothari et al. Jul 2003 B1
6591049 Williams et al. Jul 2003 B2
6593677 Behin et al. Jul 2003 B2
6600474 Heines et al. Jul 2003 B1
6621488 Takeuchi et al. Sep 2003 B1
6626540 Ouchi et al. Sep 2003 B2
6633301 Dallas et al. Oct 2003 B1
6639570 Furness, III Oct 2003 B2
6639572 Little et al. Oct 2003 B1
6650455 Miles Nov 2003 B2
6650822 Zhou Nov 2003 B1
6664779 Lopes et al. Dec 2003 B2
6666561 Blakley Dec 2003 B1
6671078 Flanders et al. Dec 2003 B2
6674562 Miles Jan 2004 B1
6677709 Ma et al. Jan 2004 B1
6677936 Jacobsen et al. Jan 2004 B2
6678029 Suzuki Jan 2004 B2
6680792 Miles Jan 2004 B2
6687040 Kimura Feb 2004 B2
6687896 Royce et al. Feb 2004 B1
6690422 Daly et al. Feb 2004 B1
6697035 Sugahara et al. Feb 2004 B2
6698348 Bloss Mar 2004 B1
6698349 Komata Mar 2004 B2
6700554 Ham et al. Mar 2004 B2
6701039 Bourgeois et al. Mar 2004 B2
6707176 Rodgers Mar 2004 B1
6710008 Chang et al. Mar 2004 B2
6710538 Ahn et al. Mar 2004 B1
6710908 Miles et al. Mar 2004 B2
6710920 Mashitani et al. Mar 2004 B1
6712071 Parker Mar 2004 B1
6712481 Parker et al. Mar 2004 B2
6731355 Miyashita May 2004 B2
6731492 Goodwin-Johansson May 2004 B2
6733354 Cathey et al. May 2004 B1
6738177 Gutierrez et al. May 2004 B1
6741377 Miles May 2004 B2
6746886 Duncan et al. Jun 2004 B2
6749312 Parker et al. Jun 2004 B2
6750930 Yoshii et al. Jun 2004 B2
6752505 Parker et al. Jun 2004 B2
6755534 Veligdan et al. Jun 2004 B2
6755547 Parker Jun 2004 B2
6760081 Takagi Jul 2004 B2
6760505 Street et al. Jul 2004 B1
6762743 Yoshihara et al. Jul 2004 B2
6762868 Liu et al. Jul 2004 B2
6764796 Fries Jul 2004 B2
6774964 Funamoto et al. Aug 2004 B2
6775048 Starkweather et al. Aug 2004 B1
6778162 Kimura et al. Aug 2004 B2
6778228 Murakami et al. Aug 2004 B2
6778248 Ootaguro et al. Aug 2004 B1
6785454 Abe Aug 2004 B2
6787969 Grade et al. Sep 2004 B2
6788371 Tanada et al. Sep 2004 B2
6794119 Miles Sep 2004 B2
6795064 Walker et al. Sep 2004 B2
6796668 Parker et al. Sep 2004 B2
6798935 Bourgeois et al. Sep 2004 B2
6800996 Nagai et al. Oct 2004 B2
6809851 Gurcan Oct 2004 B1
6819386 Roosendaal et al. Nov 2004 B2
6819465 Clikeman et al. Nov 2004 B2
6822734 Eidelman et al. Nov 2004 B1
6825470 Bawolek et al. Nov 2004 B1
6825499 Nakajima et al. Nov 2004 B2
6827456 Parker et al. Dec 2004 B2
6831678 Travis Dec 2004 B1
6832511 Samoto et al. Dec 2004 B2
6835111 Ahn et al. Dec 2004 B2
6844959 Huibers et al. Jan 2005 B2
6846082 Glent-Madsen et al. Jan 2005 B2
6846089 Stevenson et al. Jan 2005 B2
6847425 Tanada et al. Jan 2005 B2
6847428 Sekiguchi et al. Jan 2005 B1
6852095 Ray Feb 2005 B1
6857751 Penn et al. Feb 2005 B2
6859625 Sawada Feb 2005 B2
6862072 Liu et al. Mar 2005 B2
6863219 Jacobsen et al. Mar 2005 B1
6864618 Miller et al. Mar 2005 B2
6867192 Armour et al. Mar 2005 B1
6867896 Miles Mar 2005 B2
6873311 Yoshihara et al. Mar 2005 B2
6879307 Stern Apr 2005 B1
6886956 Parker et al. May 2005 B2
6887202 Currie et al. May 2005 B2
6888678 Nishiyama et al. May 2005 B2
6889565 DeConde et al. May 2005 B2
6893677 Yamada et al. May 2005 B2
6897164 Baude et al. May 2005 B2
6897843 Ayres et al. May 2005 B2
6900072 Patel et al. May 2005 B2
6906847 Huibers et al. Jun 2005 B2
6911891 Qiu et al. Jun 2005 B2
6911964 Lee et al. Jun 2005 B2
6912082 Lu et al. Jun 2005 B1
6919981 Clikeman et al. Jul 2005 B2
6934080 Saccomanno et al. Aug 2005 B2
6936013 Pevoto Aug 2005 B2
6936968 Cross et al. Aug 2005 B2
6939013 Asao Sep 2005 B2
6940631 Ishikawa Sep 2005 B2
6943495 Ma et al. Sep 2005 B2
6947107 Yoshii et al. Sep 2005 B2
6947195 Ohtaka et al. Sep 2005 B2
6950240 Matsuo Sep 2005 B2
6952301 Huibers Oct 2005 B2
6953375 Ahn et al. Oct 2005 B2
6961167 Prins et al. Nov 2005 B2
6962418 Utsumi et al. Nov 2005 B2
6962419 Huibers Nov 2005 B2
6963330 Sugahara et al. Nov 2005 B2
6965375 Gettemy et al. Nov 2005 B1
6967698 Tanoue et al. Nov 2005 B2
6967763 Fujii et al. Nov 2005 B2
6969635 Patel et al. Nov 2005 B2
6970227 Kida et al. Nov 2005 B2
6977710 Akiyama et al. Dec 2005 B2
6980349 Huibers et al. Dec 2005 B1
6985205 Chol et al. Jan 2006 B2
6992375 Robbins et al. Jan 2006 B2
6996306 Chen et al. Feb 2006 B2
7004610 Yamashita et al. Feb 2006 B2
7004611 Parker et al. Feb 2006 B2
7012726 Miles Mar 2006 B1
7012732 Miles Mar 2006 B2
7014349 Shinohara et al. Mar 2006 B2
7019809 Sekiguchi Mar 2006 B2
7026821 Martin et al. Apr 2006 B2
7038758 Suzuki May 2006 B2
7042618 Selbrede et al. May 2006 B2
7042643 Miles May 2006 B2
7046221 Malzbender May 2006 B1
7046905 Gardiner et al. May 2006 B1
7048905 Paparatto et al. May 2006 B2
7050035 Iisaka May 2006 B2
7050141 Yokoue May 2006 B2
7050219 Kimura May 2006 B2
7050790 Yamaga May 2006 B2
7057790 Selbrede Jun 2006 B2
7060895 Kothari et al. Jun 2006 B2
7071611 Yonekubo et al. Jul 2006 B2
7072096 Holman et al. Jul 2006 B2
7075702 Huibers et al. Jul 2006 B2
7092142 Selebrede et al. Aug 2006 B2
7110158 Miles Sep 2006 B2
7116464 Osawa Oct 2006 B2
7119944 Patel et al. Oct 2006 B2
7123216 Miles Oct 2006 B1
7123796 Steckl et al. Oct 2006 B2
7126738 Miles Oct 2006 B2
7140751 Lin Nov 2006 B2
7156548 Teng et al. Jan 2007 B2
7161094 Kothari et al. Jan 2007 B2
7164250 Boscolo et al. Jan 2007 B2
7164520 Palmateer et al. Jan 2007 B2
7180677 Fujii et al. Feb 2007 B2
7184202 Miles et al. Feb 2007 B2
7196837 Sampsell et al. Mar 2007 B2
7198982 Patel et al. Apr 2007 B2
7199916 Faase et al. Apr 2007 B2
7215459 Huibers et al. May 2007 B2
7217588 Hartzell et al. May 2007 B2
7218437 Selbrede May 2007 B2
7227677 Ravnkilde et al. Jun 2007 B2
7271945 Hagood et al. Sep 2007 B2
7274416 Feenstra et al. Sep 2007 B2
7291363 Miller Nov 2007 B2
7292235 Nose Nov 2007 B2
7298448 Wu Nov 2007 B2
7304785 Hagood et al. Dec 2007 B2
7304786 Hagood et al. Dec 2007 B2
7315294 Richards Jan 2008 B2
7359108 Hayes et al. Apr 2008 B2
7365897 Hagood et al. Apr 2008 B2
7374328 Kuroda et al. May 2008 B2
7391493 Kim Jun 2008 B2
7391552 Barton et al. Jun 2008 B2
7405852 Brosnihan et al. Jul 2008 B2
7417735 Cummings et al. Aug 2008 B2
7417782 Hagood et al. Aug 2008 B2
7460290 Hagood, IV et al. Dec 2008 B2
7463227 Van Gorkom Dec 2008 B2
7502159 Hagood, IV et al. Mar 2009 B2
7529012 Hayes et al. May 2009 B2
7551344 Hagood et al. Jun 2009 B2
7573547 Palmateer et al. Aug 2009 B2
7601942 Underwood et al. Oct 2009 B2
7616368 Hagood, IV Nov 2009 B2
7619806 Hagood, IV et al. Nov 2009 B2
7636189 Hagood, IV et al. Dec 2009 B2
7666049 Saito et al. Feb 2010 B2
7675665 Hagood et al. Mar 2010 B2
7715080 Natarajan et al. May 2010 B2
7729037 Hagood, IV et al. Jun 2010 B2
7742016 Hagood et al. Jun 2010 B2
7742215 Hagood, IV Jun 2010 B2
7746529 Hagood et al. Jun 2010 B2
7755582 Hagood et al. Jul 2010 B2
7826127 Khonsari et al. Nov 2010 B2
7839356 Hagood et al. Nov 2010 B2
7852546 Fijol et al. Dec 2010 B2
7876489 Gandhi et al. Jan 2011 B2
7898714 Hagood, IV et al. Mar 2011 B2
7920317 Lee et al. Apr 2011 B2
7927654 Hagood et al. Apr 2011 B2
7975665 Mori Jul 2011 B2
7999994 Hagood, IV et al. Aug 2011 B2
8159428 Hagood et al. Apr 2012 B2
8169679 Wu et al. May 2012 B2
8310442 Hagood et al. Nov 2012 B2
8698980 Chao et al. Apr 2014 B2
20010001260 Parker et al. May 2001 A1
20010028422 Tsujimura et al. Oct 2001 A1
20010028993 Sanford Oct 2001 A1
20010040538 Quanrud Nov 2001 A1
20010043177 Huston et al. Nov 2001 A1
20010043208 Furness et al. Nov 2001 A1
20010048265 Miller et al. Dec 2001 A1
20010048431 Laffargue et al. Dec 2001 A1
20010050661 Noda et al. Dec 2001 A1
20010053075 Parker et al. Dec 2001 A1
20020000959 Colgan et al. Jan 2002 A1
20020001051 Krusius et al. Jan 2002 A1
20020009275 Williams et al. Jan 2002 A1
20020012159 Tew Jan 2002 A1
20020015215 Miles Feb 2002 A1
20020024641 Ilkov et al. Feb 2002 A1
20020024711 Miles Feb 2002 A1
20020030566 Bozler et al. Mar 2002 A1
20020047172 Reid Apr 2002 A1
20020051096 Yamazaki et al. May 2002 A1
20020054424 Miles May 2002 A1
20020054487 Parker et al. May 2002 A1
20020056900 Liu et al. May 2002 A1
20020063218 Maydanich et al. May 2002 A1
20020063661 Comiskey et al. May 2002 A1
20020070931 Ishikawa Jun 2002 A1
20020075555 Miles Jun 2002 A1
20020080598 Parker et al. Jun 2002 A1
20020093722 Chan et al. Jul 2002 A1
20020109903 Kaeriyama Aug 2002 A1
20020113281 Cunningham et al. Aug 2002 A1
20020126364 Miles Sep 2002 A1
20020126387 Ishikawa et al. Sep 2002 A1
20020132389 Patel et al. Sep 2002 A1
20020135553 Nagai et al. Sep 2002 A1
20020141174 Parker et al. Oct 2002 A1
20020149828 Miles et al. Oct 2002 A1
20020150698 Kawabata Oct 2002 A1
20020163482 Sullivan Nov 2002 A1
20020163484 Furness, III Nov 2002 A1
20020163709 Mirza Nov 2002 A1
20020171327 Miller et al. Nov 2002 A1
20020181597 Okada Dec 2002 A1
20020185699 Reid Dec 2002 A1
20020191267 Flanders et al. Dec 2002 A1
20020195423 Patel et al. Dec 2002 A1
20020196522 Little et al. Dec 2002 A1
20030001815 Cui Jan 2003 A1
20030007344 Parker Jan 2003 A1
20030009898 Slocum et al. Jan 2003 A1
20030010894 Yoshihara et al. Jan 2003 A1
20030023110 Tam et al. Jan 2003 A1
20030029705 Qiu et al. Feb 2003 A1
20030036215 Reid Feb 2003 A1
20030042157 Mays Mar 2003 A1
20030043157 Miles Mar 2003 A1
20030043337 Takabayashi Mar 2003 A1
20030048036 Lemkin Mar 2003 A1
20030048370 Koyama Mar 2003 A1
20030058543 Sheedy et al. Mar 2003 A1
20030063233 Takagi Apr 2003 A1
20030063234 Oda et al. Apr 2003 A1
20030067565 Yamamura Apr 2003 A1
20030068118 Bourgeois et al. Apr 2003 A1
20030071686 Lemkin Apr 2003 A1
20030072070 Miles Apr 2003 A1
20030076649 Speakman Apr 2003 A1
20030081315 Kobayashi May 2003 A1
20030081402 Jeon et al. May 2003 A1
20030085650 Cathey et al. May 2003 A1
20030085867 Grabert May 2003 A1
20030095081 Furness, III May 2003 A1
20030095398 Parker et al. May 2003 A1
20030102810 Cross et al. Jun 2003 A1
20030123245 Parker et al. Jul 2003 A1
20030123246 Parker Jul 2003 A1
20030123247 Parker et al. Jul 2003 A1
20030128218 Struyk Jul 2003 A1
20030128416 Caracci et al. Jul 2003 A1
20030133284 Chipchase et al. Jul 2003 A1
20030137499 Iisaka Jul 2003 A1
20030152872 Miles Aug 2003 A1
20030156422 Tatewaki et al. Aug 2003 A1
20030164814 Starkweather et al. Sep 2003 A1
20030174422 Miller et al. Sep 2003 A1
20030174931 Rodgers et al. Sep 2003 A1
20030183008 Bang et al. Oct 2003 A1
20030184189 Sinclair Oct 2003 A1
20030190535 Fries Oct 2003 A1
20030190536 Fries Oct 2003 A1
20030196590 Hartzell Oct 2003 A1
20030202338 Parker Oct 2003 A1
20030210811 Dubowsky et al. Nov 2003 A1
20030218793 Soneda et al. Nov 2003 A1
20030231160 Yoshihara et al. Dec 2003 A1
20040001033 Goodwin-Johansson et al. Jan 2004 A1
20040012946 Parker et al. Jan 2004 A1
20040036668 Nakanishi Feb 2004 A1
20040051929 Sampsell et al. Mar 2004 A1
20040058532 Miles et al. Mar 2004 A1
20040076008 Ikeda Apr 2004 A1
20040080240 Miller et al. Apr 2004 A1
20040080484 Heines et al. Apr 2004 A1
20040080927 Parker et al. Apr 2004 A1
20040085608 Theil et al. May 2004 A1
20040085749 Parker et al. May 2004 A1
20040088629 Ott May 2004 A1
20040090144 Miller et al. May 2004 A1
20040090599 Kowarz et al. May 2004 A1
20040095739 Parker et al. May 2004 A1
20040100677 Huibers et al. May 2004 A1
20040113903 Mikami et al. Jun 2004 A1
20040114346 Parker et al. Jun 2004 A1
20040122328 Wang et al. Jun 2004 A1
20040125062 Yamamoto et al. Jul 2004 A1
20040125346 Huibers Jul 2004 A1
20040135273 Parker et al. Jul 2004 A1
20040135951 Stumbo et al. Jul 2004 A1
20040136204 Asao Jul 2004 A1
20040136680 Medina et al. Jul 2004 A1
20040141700 Yang Jul 2004 A1
20040145580 Perlman Jul 2004 A1
20040145854 Tamura Jul 2004 A1
20040156246 Nakamura Aug 2004 A1
20040157664 Link Aug 2004 A1
20040165372 Parker Aug 2004 A1
20040171206 Rodgers Sep 2004 A1
20040173872 Park et al. Sep 2004 A1
20040179146 Nilsson Sep 2004 A1
20040184710 Kubby et al. Sep 2004 A1
20040196215 Duthaler et al. Oct 2004 A1
20040196525 Fujii et al. Oct 2004 A1
20040207768 Liu Oct 2004 A1
20040207815 Allen et al. Oct 2004 A1
20040212759 Hayashi Oct 2004 A1
20040212907 Mala et al. Oct 2004 A1
20040217919 Piehl et al. Nov 2004 A1
20040218149 Huibers Nov 2004 A1
20040218154 Huibers Nov 2004 A1
20040218292 Huibers Nov 2004 A1
20040218293 Huibers Nov 2004 A1
20040223088 Huibers Nov 2004 A1
20040223240 Huibers Nov 2004 A1
20040227428 Sinclair Nov 2004 A1
20040233354 Uehara et al. Nov 2004 A1
20040233392 Huibers Nov 2004 A1
20040233498 Starkweather et al. Nov 2004 A1
20040233503 Kimura Nov 2004 A1
20040240032 Miles Dec 2004 A1
20040240138 Martin et al. Dec 2004 A1
20040246275 Yoshihara et al. Dec 2004 A1
20040263076 De Zwart et al. Dec 2004 A1
20040263502 Dallas et al. Dec 2004 A1
20040263944 Miles et al. Dec 2004 A1
20050002082 Miles Jan 2005 A1
20050002086 Starkweather et al. Jan 2005 A1
20050007671 Onvlee Jan 2005 A1
20050007759 Parker Jan 2005 A1
20050012197 Smith et al. Jan 2005 A1
20050018322 Ben-Gad et al. Jan 2005 A1
20050024849 Parker et al. Feb 2005 A1
20050052681 Kogi Mar 2005 A1
20050052723 Watanabe et al. Mar 2005 A1
20050059184 Sniegowski et al. Mar 2005 A1
20050062708 Yoshihara et al. Mar 2005 A1
20050063037 Selebrede et al. Mar 2005 A1
20050072032 McCollum et al. Apr 2005 A1
20050073471 Selbrede Apr 2005 A1
20050088404 Heines et al. Apr 2005 A1
20050093465 Yonekubo et al. May 2005 A1
20050094240 Huibers et al. May 2005 A1
20050094418 Parker May 2005 A1
20050104804 Feenstra et al. May 2005 A1
20050111238 Parker May 2005 A1
20050111241 Parker May 2005 A1
20050116798 Bintoro et al. Jun 2005 A1
20050122560 Sampsell et al. Jun 2005 A1
20050122591 Parker et al. Jun 2005 A1
20050123243 Steckl et al. Jun 2005 A1
20050123249 Yun et al. Jun 2005 A1
20050123349 Koch Jun 2005 A1
20050128370 Moon Jun 2005 A1
20050134768 Sugiura et al. Jun 2005 A1
20050134805 Conner et al. Jun 2005 A1
20050139542 Dickensheets et al. Jun 2005 A1
20050140636 Chung et al. Jun 2005 A1
20050141076 Bausenwein et al. Jun 2005 A1
20050151940 Asao Jul 2005 A1
20050157365 Ravnkilde et al. Jul 2005 A1
20050157376 Huibers et al. Jul 2005 A1
20050168431 Chui Aug 2005 A1
20050168789 Glent-Madsen Aug 2005 A1
20050171408 Parker Aug 2005 A1
20050172625 Starkweather et al. Aug 2005 A1
20050179977 Chui et al. Aug 2005 A1
20050195467 Kothari et al. Sep 2005 A1
20050195468 Sampsell Sep 2005 A1
20050206991 Chui et al. Sep 2005 A1
20050207154 Parker Sep 2005 A1
20050207178 Parker Sep 2005 A1
20050212734 Kimura Sep 2005 A1
20050212738 Gally Sep 2005 A1
20050213183 Miles Sep 2005 A9
20050213322 Parker Sep 2005 A1
20050213323 Parker Sep 2005 A1
20050213349 Parker Sep 2005 A1
20050219676 Kimura et al. Oct 2005 A1
20050219679 Ishikawa Oct 2005 A1
20050219680 Ishikawa Oct 2005 A1
20050225501 Srinivasan et al. Oct 2005 A1
20050225519 Naugler, Jr. Oct 2005 A1
20050225732 Conner et al. Oct 2005 A1
20050225827 Kastalsky Oct 2005 A1
20050231790 Miles Oct 2005 A1
20050231791 Sampsell et al. Oct 2005 A1
20050236928 Kurozuka et al. Oct 2005 A1
20050237596 Selbrede Oct 2005 A1
20050242710 Yamazaki et al. Nov 2005 A1
20050243023 Reddy et al. Nov 2005 A1
20050244099 Pasch et al. Nov 2005 A1
20050244949 Miles Nov 2005 A1
20050245313 Yoshino et al. Nov 2005 A1
20050247477 Kothari et al. Nov 2005 A1
20050249966 Tung et al. Nov 2005 A1
20050253779 Feenstra et al. Nov 2005 A1
20050254115 Palmateer et al. Nov 2005 A1
20050258571 Dumond et al. Nov 2005 A1
20050259198 Lubart et al. Nov 2005 A1
20050263866 Wan Dec 2005 A1
20050265029 Epstein et al. Dec 2005 A1
20050275072 Haluzak et al. Dec 2005 A1
20050275930 Patel et al. Dec 2005 A1
20050285816 Glass Dec 2005 A1
20050286113 Miles Dec 2005 A1
20050286114 Miles Dec 2005 A1
20060001942 Chui et al. Jan 2006 A1
20060003676 Bernard et al. Jan 2006 A1
20060004928 Hess et al. Jan 2006 A1
20060007514 Desai Jan 2006 A1
20060007701 Schoellmann et al. Jan 2006 A1
20060012781 Fradkin et al. Jan 2006 A1
20060023287 Przybyla et al. Feb 2006 A1
20060028708 Miles Feb 2006 A1
20060028811 Ross, Jr. et al. Feb 2006 A1
20060028817 Parker Feb 2006 A1
20060028840 Parker Feb 2006 A1
20060028841 Parker Feb 2006 A1
20060028843 Parker Feb 2006 A1
20060028844 Parker Feb 2006 A1
20060033676 Faase et al. Feb 2006 A1
20060033975 Miles Feb 2006 A1
20060038766 Morita Feb 2006 A1
20060038768 Sagawa et al. Feb 2006 A1
20060044246 Mignard Mar 2006 A1
20060044298 Mignard et al. Mar 2006 A1
20060044508 Mochizuki Mar 2006 A1
20060044928 Chui et al. Mar 2006 A1
20060061559 King Mar 2006 A1
20060066504 Sampsell et al. Mar 2006 A1
20060066540 Hewlett et al. Mar 2006 A1
20060066560 Gally et al. Mar 2006 A1
20060066598 Floyd Mar 2006 A1
20060066934 Selbrede Mar 2006 A1
20060066937 Chui Mar 2006 A1
20060077125 Floyd Apr 2006 A1
20060077153 Cummings et al. Apr 2006 A1
20060077533 Miles et al. Apr 2006 A1
20060092490 McCollum et al. May 2006 A1
20060104061 Lerner et al. May 2006 A1
20060132383 Gally et al. Jun 2006 A1
20060132404 Hayes et al. Jun 2006 A1
20060139734 Selebrede et al. Jun 2006 A1
20060146389 Selbrede Jul 2006 A1
20060152476 Van Gorkom et al. Jul 2006 A1
20060154078 Watanabe et al. Jul 2006 A1
20060172745 Knowles Aug 2006 A1
20060187190 Hagood et al. Aug 2006 A1
20060187191 Hagood et al. Aug 2006 A1
20060187290 Nakashima Aug 2006 A1
20060187528 Hagood et al. Aug 2006 A1
20060209000 Sumiyoshi et al. Sep 2006 A1
20060209012 Hagood, IV Sep 2006 A1
20060238443 Derichs Oct 2006 A1
20060250325 Hagood et al. Nov 2006 A1
20060250676 Hagood Nov 2006 A1
20060256039 Hagood et al. Nov 2006 A1
20060262060 Amundson Nov 2006 A1
20060262380 Miles Nov 2006 A1
20060268386 Selbrede et al. Nov 2006 A1
20060268568 Oku et al. Nov 2006 A1
20060270179 Yang Nov 2006 A1
20060280319 Wang et al. Dec 2006 A1
20060291034 Patry et al. Dec 2006 A1
20060291771 Braunisch et al. Dec 2006 A1
20060291774 Schoellmann et al. Dec 2006 A1
20070002156 Hagood et al. Jan 2007 A1
20070002413 Psaltis et al. Jan 2007 A1
20070003055 Bark et al. Jan 2007 A1
20070007889 Bongaerts et al. Jan 2007 A1
20070024701 Prechtl et al. Feb 2007 A1
20070030555 Barton et al. Feb 2007 A1
20070031097 Heikenfeld et al. Feb 2007 A1
20070035808 Amundson et al. Feb 2007 A1
20070040982 Nakano et al. Feb 2007 A1
20070047051 Selbrede et al. Mar 2007 A1
20070047887 Selbrede Mar 2007 A1
20070052636 Kalt et al. Mar 2007 A1
20070052660 Montbach et al. Mar 2007 A1
20070053652 Mignard et al. Mar 2007 A1
20070086078 Hagood et al. Apr 2007 A1
20070091011 Selbrede Apr 2007 A1
20070091038 Hagood et al. Apr 2007 A1
20070103209 Lee May 2007 A1
20070127108 Hayes et al. Jun 2007 A1
20070132680 Kagawa et al. Jun 2007 A1
20070150813 Selebrede et al. Jun 2007 A1
20070159679 Hagood et al. Jul 2007 A1
20070172171 Van Ostrand et al. Jul 2007 A1
20070190265 Aoki et al. Aug 2007 A1
20070195026 Hagood et al. Aug 2007 A1
20070205969 Hagood, IV et al. Sep 2007 A1
20070217108 Ozawa et al. Sep 2007 A1
20070223080 Hagood et al. Sep 2007 A1
20070247401 Sasagawa et al. Oct 2007 A1
20070279727 Gandhi et al. Dec 2007 A1
20070297747 Biernath et al. Dec 2007 A1
20080014557 Kuhn et al. Jan 2008 A1
20080026066 Roser Jan 2008 A1
20080030827 Hagood et al. Feb 2008 A1
20080037104 Hagood et al. Feb 2008 A1
20080043726 Herrero-Veron et al. Feb 2008 A1
20080062500 Hagood Mar 2008 A1
20080094853 Kim et al. Apr 2008 A1
20080123175 Hagood et al. May 2008 A1
20080129681 Hagood et al. Jun 2008 A1
20080158635 Hagood et al. Jul 2008 A1
20080158636 Hagood et al. Jul 2008 A1
20080165122 Duthaler et al. Jul 2008 A1
20080174532 Lewis Jul 2008 A1
20080278798 Hagood et al. Nov 2008 A1
20080279727 Haushalter Nov 2008 A1
20080283175 Hagood et al. Nov 2008 A1
20080297880 Steckl et al. Dec 2008 A1
20090034052 Hagood et al. Feb 2009 A1
20090091561 Koyama Apr 2009 A1
20090103164 Fijol et al. Apr 2009 A1
20090103281 Koh Apr 2009 A1
20090141335 Feenstra et al. Jun 2009 A1
20090195855 Steyn et al. Aug 2009 A1
20090284824 Feenstra et al. Nov 2009 A1
20100328608 Fujii et al. Dec 2010 A1
20110122474 Payne et al. May 2011 A1
20110148948 Gandhi et al. Jun 2011 A1
20110205259 Hagood, IV Aug 2011 A1
20110255146 Brosnihan et al. Oct 2011 A1
20110267668 Hagood, IV et al. Nov 2011 A1
20120133006 Hasselbach et al. May 2012 A1
20120169795 Hagood et al. Jul 2012 A1
20120200906 Wu et al. Aug 2012 A1
20120229226 Oja et al. Sep 2012 A1
20120280971 Hagood et al. Nov 2012 A1
20120320111 Hagood, IV et al. Dec 2012 A1
20120320112 Hagood, IV et al. Dec 2012 A1
20120320113 Hagood, IV et al. Dec 2012 A1
20130010341 Hagood et al. Jan 2013 A1
20130010342 Hagood, IV et al. Jan 2013 A1
20130010344 Hagood et al. Jan 2013 A1
20130335806 Steyn et al. Dec 2013 A1
20130342522 Hagood Dec 2013 A1
20140085698 Wu et al. Mar 2014 A1
20140268293 Chleirigh et al. Sep 2014 A1
Foreign Referenced Citations (225)
Number Date Country
2241823 Aug 1997 CA
2334403 Dec 1999 CA
1206218 Jan 1999 CN
1309782 Aug 2001 CN
1390045 Jan 2003 CN
1402033 Mar 2003 CN
1498408 May 2004 CN
1542499 Nov 2004 CN
1555472 Dec 2004 CN
1898969 Jan 2007 CN
10332647 Feb 2005 DE
0366847 May 1990 EP
0438614 Jul 1991 EP
0359450 Nov 1994 EP
0495273 Sep 1996 EP
0415625 Jan 1997 EP
0786679 Jul 1997 EP
0884525 Dec 1998 EP
0889458 Jan 1999 EP
0751340 May 2000 EP
1022598 Jul 2000 EP
1 091 342 Apr 2001 EP
1091343 Apr 2001 EP
1091842 Apr 2001 EP
1093142 Apr 2001 EP
1168051 Jan 2002 EP
1202096 May 2002 EP
1202244 May 2002 EP
1426190 Jun 2004 EP
1429310 Jun 2004 EP
1471495 Oct 2004 EP
1522883 Apr 2005 EP
1533853 May 2005 EP
1551002 Jul 2005 EP
1674893 Jun 2006 EP
1734502 Dec 2006 EP
1757958 Feb 2007 EP
2263968 Dec 2010 EP
1858796 Jan 2011 EP
2287110 Feb 2011 EP
1640770 Apr 2012 EP
2459777 Jun 2012 EP
2726135 Apr 1996 FR
2071896 Sep 1981 GB
2343980 May 2000 GB
S56137386 Oct 1981 JP
57062028 Apr 1982 JP
S5774730 May 1982 JP
57127264 Aug 1982 JP
S5933077 Feb 1984 JP
S62275230 Nov 1987 JP
3142409 Jun 1991 JP
4249203 Sep 1992 JP
5045648 Feb 1993 JP
H06174929 Jun 1994 JP
6194649 Jul 1994 JP
H06202009 Jul 1994 JP
H06222290 Aug 1994 JP
H06250593 Sep 1994 JP
H0836161 Feb 1996 JP
H0895526 Apr 1996 JP
8234158 Sep 1996 JP
8334752 Dec 1996 JP
H08334752 Dec 1996 JP
9080386 Mar 1997 JP
09189869 Jul 1997 JP
9198906 Jul 1997 JP
H09218360 Aug 1997 JP
H09292576 Nov 1997 JP
H1054916 Feb 1998 JP
H1054947 Feb 1998 JP
10282474 Oct 1998 JP
H10282521 Oct 1998 JP
H10333145 Dec 1998 JP
11015393 Jan 1999 JP
11024038 Jan 1999 JP
H1184419 Mar 1999 JP
H1195693 Apr 1999 JP
H11126118 May 1999 JP
H11202325 Jul 1999 JP
2000028933 Jan 2000 JP
2000028938 Jan 2000 JP
2000057832 Feb 2000 JP
2000105547 Apr 2000 JP
2000111813 Apr 2000 JP
2000121970 Apr 2000 JP
2000131627 May 2000 JP
2000172219 Jun 2000 JP
2000214393 Aug 2000 JP
2000214394 Aug 2000 JP
2000214395 Aug 2000 JP
2000214397 Aug 2000 JP
2000214831 Aug 2000 JP
2000235152 Aug 2000 JP
2000259116 Sep 2000 JP
2000321566 Nov 2000 JP
2001067010 Mar 2001 JP
2001075534 Mar 2001 JP
2001100121 Apr 2001 JP
2001125014 May 2001 JP
2001154642 Jun 2001 JP
2001175216 Jun 2001 JP
2001201698 Jul 2001 JP
2001201767 Jul 2001 JP
2001242826 Sep 2001 JP
2001281563 Oct 2001 JP
2001318377 Nov 2001 JP
2001331142 Nov 2001 JP
2001331144 Nov 2001 JP
2001337649 Dec 2001 JP
2001356281 Dec 2001 JP
2001356327 Dec 2001 JP
2002040336 Feb 2002 JP
2002040337 Feb 2002 JP
2002139683 May 2002 JP
2002140038 May 2002 JP
2002214543 Jul 2002 JP
2002279812 Sep 2002 JP
2002528763 Sep 2002 JP
2002287718 Oct 2002 JP
2002297085 Oct 2002 JP
2002318564 Oct 2002 JP
2002333619 Nov 2002 JP
2002341343 Nov 2002 JP
2002351431 Dec 2002 JP
2002365650 Dec 2002 JP
2003029295 Jan 2003 JP
2003036057 Feb 2003 JP
2003506755 Feb 2003 JP
2003084314 Mar 2003 JP
2003086233 Mar 2003 JP
2003098984 Apr 2003 JP
2003121824 Apr 2003 JP
2003162904 Jun 2003 JP
2003202519 Jul 2003 JP
2003248463 Sep 2003 JP
2003344785 Dec 2003 JP
2004004216 Jan 2004 JP
2004053839 Feb 2004 JP
2004069788 Mar 2004 JP
2004117833 Apr 2004 JP
2004140800 May 2004 JP
2004151722 May 2004 JP
2004163915 Jun 2004 JP
2004191736 Jul 2004 JP
2004205973 Jul 2004 JP
2004212673 Jul 2004 JP
2004221051 Aug 2004 JP
2004287215 Oct 2004 JP
2004287431 Oct 2004 JP
2004302270 Oct 2004 JP
2004317557 Nov 2004 JP
2004317785 Nov 2004 JP
2004325909 Nov 2004 JP
2004327025 Nov 2004 JP
2004534280 Nov 2004 JP
2004347982 Dec 2004 JP
2005010786 Jan 2005 JP
2005043674 Feb 2005 JP
2005043726 Feb 2005 JP
2005504355 Feb 2005 JP
2005512119 Apr 2005 JP
2005134896 May 2005 JP
2005309416 Nov 2005 JP
2006522360 Sep 2006 JP
2007155983 Jun 2007 JP
2007517488 Jun 2007 JP
2008015081 Jan 2008 JP
2008098984 Apr 2008 JP
2008233898 Oct 2008 JP
2009111813 May 2009 JP
2012128451 Jul 2012 JP
2012186782 Sep 2012 JP
2012230079 Nov 2012 JP
WO9401716 Jan 1994 WO
9528035 Oct 1995 WO
WO9704436 Feb 1997 WO
WO9804950 Feb 1998 WO
WO-9819201 May 1998 WO
WO9901696 Jan 1999 WO
WO-0017695 Mar 2000 WO
WO0050807 Aug 2000 WO
WO0052674 Sep 2000 WO
WO0055916 Sep 2000 WO
WO0169584 Sep 2001 WO
WO0207482 Jan 2002 WO
WO03004836 Jan 2003 WO
WO03007049 Jan 2003 WO
WO03008860 Jan 2003 WO
WO-03029874 Apr 2003 WO
WO03040802 May 2003 WO
WO03048836 Jun 2003 WO
WO03050448 Jun 2003 WO
WO-03061007 Jul 2003 WO
WO03061329 Jul 2003 WO
WO03069593 Aug 2003 WO
WO03081315 Oct 2003 WO
WO-03105198 Dec 2003 WO
WO2004008629 Jan 2004 WO
WO2004019120 Mar 2004 WO
WO2004034136 Apr 2004 WO
WO-2004038496 May 2004 WO
WO2004086098 Oct 2004 WO
WO2004088629 Oct 2004 WO
2004097506 Nov 2004 WO
WO2005001892 Jan 2005 WO
WO2005062908 Jul 2005 WO
WO2005073950 Aug 2005 WO
WO2005082908 Sep 2005 WO
WO2006017129 Feb 2006 WO
WO2006023077 Mar 2006 WO
WO2006039315 Apr 2006 WO
WO2006052755 May 2006 WO
2006091738 Aug 2006 WO
2006091904 Aug 2006 WO
WO2006091791 Aug 2006 WO
WO-2006091860 Aug 2006 WO
WO2007075832 Jul 2007 WO
WO2007123173 Nov 2007 WO
WO2007145973 Dec 2007 WO
WO2008026066 Mar 2008 WO
WO-2008091339 Jul 2008 WO
WO-2009102471 Aug 2009 WO
2010062647 Jun 2010 WO
WO-2013032865 Mar 2013 WO
Non-Patent Literature Citations (109)
Entry
Akimoto, et al. “15.1: A 0.9-in UXGA/HDTV FLC Microdisplay,” Society for Information Display, pp. 194-197 (2000).
Alt et al, “A Gray-Scale Addressing Technique for Thin-Film-Transistor/Liquid Crystal Displays,” IBM J. Res. Develop., 36(1):11-22 (Jan. 1992).
Chino, E., et al., “25.1: Invited Paper: Development of Wide-Color-Gamut Mobile Displays with Four-primary-color LCDs,” Society for Information Display, 37(2):1221-1224 (2006).
Clark et al, “FLC Microdisplays,” Ferroelectrics, 246:97-110 (2000).
den Boer, W., “Active Matrix Liquid Crystal Displays,” Elsevier Science & Technology Books, ISBN #750678135, Aug. 2005.
Doherty, D., et al., “Pulse width modulation control in DLP™ projectors,” TI Technical Journal, No. 3, pp. 115-121 (Jul.-Sep. 1998).
Feenstra et al, “Electrowetting Displays,” Liquavista BV, pp. 1-16 (Jan. 2006). http://www.liquavista.com/documents/electrowetting—displays—whitepaper.pdf, Retrieved on Aug. 17, 2006.
Hornbeck, “Digital Light Processing™: A New MEMS-Based Display Technology,” Technical Digest of the IEEJ 14th Sensor Symposium, pp. 297-304 (Jun. 4-5, 1996).
Kunzman, A., et al., “10.3 White Enhancement for Color Sequential DLP™,” Society for Information Display (1998).
Markandey, V., et al., Video Processing for DLP Display Systems, Texas Instruments Corporation, 2666:21-32 (Mar. 13, 1996).
Ravnkilde et al, “Fabrication of Nickel Microshutter Arrays for Spatial Light Modulation” Meso 2002, also on their web site: http://www2.mic.dtu.dk/research/mems/publications/Papers/Dicon—Meso2002.pdf (2002).
Takatori et al, “6.3: Field-Sequential Smectic LCD with TFT Pixel Amplifier,” SID 01 Digest, 48-51 (2001).
Wang et al, “Highly Space-Efficient Electrostatic Zigzag Transmissive Micro-Optic Switches for an Integrated MEMS Optical Display System,” Transducers 03 Conference, 1:575-575 (Jun. 8-12, 2003).
AZ Displays, Inc., “Complete LCD Solutions,” ATM3224C-NC-FTH, pp. 1-15 (Oct. 2, 2003).
Bergquist et al., “Field Sequential Colour Display with Adaptive Gamut”, Society for Information Display, Digest of Technical Papers, 2006, pp. 1594-1597.
Birch et al, “31.1: SXGA Resolution FLC Microdisplays,” SID 02 Digest, 954-957 (2002).
B.J. Feenstra et. al. “A Reflective Display Based on Electrowetting: Principle and Properties”, International Display Research Conference Proceedings 2003, p. 322.
Blackstone, “Making MEMS Reliable,” SPIE's OEMagazine, 32-34 (Sep. 2002).
BLU, Heesung Precision Ltd., http://www.hspr.co.kr/eng/product/blu.asp Retrieved on Aug. 3, 2006.
Boeuf, J.P., “Plasma display panels: physics,recent deveopments and key issues,” J. Phys. D: Appl. Phys. 36 (2003) R53-R79 (received Aug. 29, 2002: published Feb. 26, 2003).
Boucinha, M., et al., “Air-gap amorphous silicon thin film transistors,” Applied Physics Letters, 73 (4): 502-4 (Jul. 27, 1998).
Bozler et al, “Arrays of gated field-emitter cones having 0.32 mm tip-to-tip spacing,” J. Vec. Sci. Technol. B, 12 (2): 629-632 (Mar./Apr. 1994).
Bryan-Brown, “Ultra Low Power Bistable LCDs,” SID 00, 76-79 (2000).
Conde, J.P., et. al., “Amorphous and microcrystalline silicon deposited by hot-wire chemical vapor deposition at low substrate temperatures: application to devices and thin-film microelectromechanical systems,” Thin Solid Films 395: 105-111 (2001).
Conde, J.P., et al., “Low-temperature Thin-film Silicon MEMS”, in Thin Solid Films 427, p. 181 (2003).
Davis, “Light Emitting Diode Source Modeling for Optical Design,” Reflexite Display Optics (Oct. 2004).
Davis, “Microstructured Optics for LED Applications,” Reflexite Display Optics (2002).
Doane, et al, “Display Technologies in Russia, Ukraine, and Belarus,” World Technology Evaluation Center Panel Report (Dec. 1994) http://www.wtec.org/loyola/displays/toc.htm, retrieved on Nov. 22, 2005.
“Electronic Display Lighting Tutorials,” 3M Corporation,file//D:/Optical/VikuitiTutorial.htm. retrieved on Aug. 10, 2006.
Feng, et al, “Novel Integrated Light-Guide Plates for Liquid Crystal Display Backlight,” Journal of optics a Pure and applied optics, 2005, 7, 111-117.
Feng, “High Quality Light Guide Plates that Can Control the Illumination Angle Based on Microprism Structures,” Applied Physics Letters, 85 (24): 6016-6018 (Dec. 2004).
Final Office Action dated May 18, 2007, U.S. Appl. No. 11/218,690.
Final Office Action dated Oct. 3, 2007 in U.S. Appl. No. 11/218,690.
Final Office Action dated Sep. 21, 2007, U.S. Appl. No. 11/546,937.
Foley, “NE04-21: Microstructured Plastic Optics for Display, Lighting, and Telecommunications Applications,” Fresnel Optics (2001).
Funamoto et al, “Diffusive-sheetless Backlight System for Mobile Phone,” IDW/AD, 1277-1280 (2005).
Funamoto et. al. “LED Backlight System with Double-Prism Pattern”, Journal of the Society for Information Display v. 14, pp. 1045-1051 (2006).
Goddhue et al, “Bright-field analysis of field-emission cones using high-resolution tranmission electron microscopy and the effect of structural properties on current stability,” J. Vac. Sci. Technol. B, 12 (2): 693-696 (Mar.Apr. 1994).
Hartman, “4.1: Invited paper: Two-Terminal Devices Technologies for AMLCDs,” SID 95 Digest, 7-10 (1995).
Hewlett et al, “DLP CinemaTM projection: A hybrid frame-rate technique for flicker-free performance,” Journ of the SID 9/3, 221-226 (2001).
J. Heikenfeld et. al., “Contrast Enhancement in Black Dielectric Electroluminescent Devices”, IEEE Transactions on Electron Devices, 49: 8, 1348-52 (2002).
Jepsen et al, “4.11: 0.9″ SXGA Liquid Crystal on Silicon Panel with 450 Hz. Field Rate,” SID MicroDisplay Corporation, pp. 106-109 (Sep. 2001).
Joaquirn, M., “Polyphenyl Ether Lubricants” Synthetic Lubricants and High-performance Functional Fluids, R. L. Rudnick and R. L. Shubkin, Eds., p. 239, Marcel Dekker, Inc., NY, 1999.
Johnstone et al, “Theoretical limits on the freestanding length of cantilevers produced by surface micromachining technology,” J. Micromech. Microeng. 12: 855-861 (Published Oct. 3, 2002).
Jones et al, “29-1: Addressing TVmin Ferroelectric Liquid Crystal Displays,” (1998).
Judy, et al, “Self-Adjusting Microstructures(SAMS),” Proceedings of the Workshop on Micro Electro Mechanical Systems, New York, Jan. 30, 1991, vol. Workshop 4, pp. 51-56.
Judy, M. W., “Micromechanisms Using Sidewall Beams,” Dissertation, University of California at Berkeley, 1994.
Kalantar et al, “Optical Micro Deflector Based Functional Light-Guide Plate for Backlight Unit,” SID 00 Digest, 1029-1031 (2000).
Kalantar, K., et al., “Backlight Unit with Double Surface Light Emission Using a Single Micro-structured Light-guide Plate,” p. 1182, Society for Information Display Digest (2004).
Kalantar, “Modulation of viewing angle on an LCD surface through backlight optics,” Journal of the SID, 11 (4): 647-652 (2003).
Kim, C.W., et al., “Manufacturing Technologies for the Next Generation a-Si TFT-LCD,” Proceedings of the Intl. Display Mfg. Cnf. Seoul, Korea (2000).
Koden et al., “Ferroelectric Liquid Crystal Display,” (Sep. 17, 1997).
Kuang et al., “Dynamic characteristics of shaped micro-actuators solved using the differential quadrature method,” Journal of Micromechanics and Microengineering, 14: 647-655, (2004).
Lee, et al., “40.1: Distingusihed Contributed Paper: Integrated Amorphous Silicon Color Sensor on LCD Panel for LED Backlight Feedback Control System”, Society for Information Display, Digest of Technical Papers, 2005, pp. 1376-1379.
Lee et al, “P-25: A LCOS Microdisplay Driver with Frame Buffering Pixels,” SID 02 Digest, 292-295 (2002).
Legtenberg, et al., “Electrostatic Curved Electrode Actuators,” Journal of Microelectromechanical Systems, 6 (3): 257-265 (Sep. 1997).
Li, J., et al., “DRIE-Fabricated Curved-Electrode Zipping Actuators with Low Pull-In Voltage,” 12th International Conference on Solid State Sensors, Actuators and Microsystems, IEE, 480-483 (2003).
Liang et al, “Observation of electric field gradients near field-emission cathode arrays,” Appl Phys. Lett., 66 (9): 1147-1149 (Feb. 27, 1995).
Liu et al, “Scaling Laws of Microactuators and Potential Applications of Electroactive Polymers in MEMS,” SPIE, 3669: 345-354 (Mar. 1999).
Maboudian et al., “Stiction reduction processes for surface micromachines,” Tribology Letters, 3: 215-221 (1997).
Forces—Part I: Basic Theory, Journal of Microelectromechanical Systems, 2 (1): 33-43 (Mar. 1993).
Mastrangelo et al, “Mechanical Stability and Adhesion of Microstructures Under Capillary Forces—Part II: Experiments,” Journal of Microelectromechanical Systems, 2 (1): 44-55 (Mar. 1993).
McLaughlin, “Progress in Projection and Large-Area Displays,” Proceedings of the IEEE, 90 (4): 521-532 (Apr. 2002).
“MicroLensTm—Re-Inventing LCD Backlighting,” Global Lighting Technologies Inc., http://www.glthome.com/tech.htm, 1-2; retrieved on Aug. 3, 2006.
“Microprism Technology for Luminaires,” Reflexite Display Optics (2004).
“Nano TM Su-8 2000 Negative Tone Photoresist Formulations 2002-2025,” Micro Che, Rev. 2/02m.
Non Final Office Action Dated Mar. 22, 2007, U.S. Appl. No. 11/546,937.
Non Final Office Action dated Nov. 1, 2006, U.S. Appl. No. 11/218,690.
Notice of Allowance and Fee(s) Due, mailed Jan. 31, 2008 (U.S. Appl. No. 11/361,785).
Office Action dated Dec. 5, 2011 in Japanese Patent Application No. 2008-058190.
Office Action dated Jul. 15, 2010 in Japanese Patent Application No. 2007-556427.
Office Action dated Mar. 28, 2012 in European Patent Office Application No. 07795777.7.
Office Action dated Oct. 14, 2010 in Japanese Patent Application No. 2008-058190.
Office Action dated Sep. 16, 2011 in Japanese Patent Application No. 2007-556428.
Okumura et al, “Highly-efficient backlight for liquid crystal display having no optical films,” Applied Physics Letters, 83 (13): 2515-2517 (Sepember 29, 2003).
“Optical Design Tools for Backlight Displays,” Light Tools, Optical Engineering, Publication of ROCOES, 81: 90-101 (Jun. 2003).
Park, Y.I., et al., “Active Matrix OLED Displays Using Simple Poly-Si TFT Process,” Society of Information Display, Digest, pp. 487-489 (2003).
Perregaux, G., et al, “Arrays of Addressable High-Speed Optical Microshutters,” CSEM Swiss Center for Electronics and Microtechnology Inc., Microsystems Division, pp. 232-235 (2001).
“Prism Brightness Enhancement Films,” 3M Corporation, http://products3.3m.com/catalog/us/en001/electronics—mfg/vikuiti/node—V6G78RBQ5Tbe/root—GST1T4S9TCgv/vroot—S6Q2FD9X0Jge/gvel—GD378DOHGJgl/theme—us—vikuiti—3—0/command—AbcPageHandler/ output—html Retrieved on Aug. 3, 2006.
“Prism Sheet,” Mitsubishi Rayon America Inc., http://www.mrany.com/data/HTML/29.htm Retrieved on Aug. 4, 2006.
Qiu et al, “A Curved-Beam Bistable Mechanism,” Journal of Microelectromechanical Systems, 13 (2): 137-145 (Apr. 2004).
Qiu et al, “A High-Current Electrothermal Bistable MEMS Relay,” Micro Electro Mechanical Systems, MEMS-03 Kyoto, pp. 64-67 (Jan. 19-23, 2003).
Roosendaal et al, “25.2: A Wide Gamut, High Aperture Mobile Spectrum Sequential Liquid Crystal Display,” SID 05 Digest, 1116-1119 (2005).
Saeedi, et. al. “Molten-Alloy Driven Self-Assembly for Nano and Micro Scale System Integration” Fluid Dynamics and Materials Processing, vol. 2, No. 4, pp. 221-245 (2006).
Sato, “Research on Flexible Display Systems,” Broadcast Technology, 21: 10-15 (Winter, 2005).
Sharp Specification No. LCP-03015 for Mobile Liquid Crystal Display Group, Sharp Corporation, Jun. 13, 2003.
Shikida et al, “Fabrication of an S-shaped Microactuator,” Journal of Microelectromechanical Systems, 6 (1): 18-24 (Mar. 1997).
Steyn, Lodewyck, “Electroquasistatic Zipper Actuators: A Technology Review”, Dec. 2004.
Tagaya et al., “Thin Liquid-Crystal Display Backlight System with Highly Scattering Optical Transmission Polymers,” Applied Optics, 40 (34): 6274-6280 (Dec. 2001).
Tan et al “Soldering Technology for Optoelectronics Packaging”, 1996 Electronic Components and Technology Conference, pp. 26-36 (1996).
Teijido, J.M., “Conception and Design of Illumination Light Pipes,” Thesis No. 1498 for University of Neuchatel, http://www.unige.ch/cyberdocuments/unine/theses2000/TeijidoJM/these—front.htm 1: 1-99 Retrieved on Aug. 3, 2006.
Tien et al, “MEMS Actuators for Silicon Micro-Optical Elements,” Proc. of SPIE, 4178: 256-269, (2000).
“Two Proprietary Technologies Supporting OMRON Backlight,” OMRON Electronics Corporation, OMROM Electronics Components Web, www.omron.co.jp/ecb/products/bklight/english/genri/index.html, retrieved on Aug. 3, 2006.
Underwood, “A review of microdisplay technologies,” SID © EID, (Nov. 21 to 23, 2000).
Underwood, “LCoS through the looking glass,” SID (2001).
van de Biggelaar, et. al. “Passive and Active Matrix Addressed Polymer Light-emitting Diode Displays”, Proc. SPIE vol. 4295, p. 134 (2001).
Vangbo et al, “A lateral symmetrically bistable buckled beam,” J. Micromech. Microeng., 8: 29-32 (1998).
Wang et al., “A highly efficient system for automatic face region detection in MPEG video.” IEEE Trans. on Circuits and Systems for Video Technology, vol. 7 Issue 4, Aug. 1997, pp. 615-628.
Yamada et al, “52.2: Invited Paper: Color Sequential LCD Based on OCB with an LED Backlight,” SID 00 Digest, 1180-1183 (2000).
Yasumura et al, “Fluid Damping of an Electrostatic Actuator for Optical Switching Applications,” Transducers Research Foundation (2002).
Extended European Search Report dated Mar. 15, 2013 in EP Application No. EP12181160.8.
Mastrangelo et al, “Mechanical Stability and Adhesion of Microstructures Under Capillary Forces—Part I: Basic Theory,” Journal of Microelectromechanical Systems, 2 (1): 33-43 (Mar. 1993).
Pasricha S. et al., “Dynamic Backlight Adaptation for Low Power Handheld Devices” IEEE Design and Test v. 21, 2004, pp. 398.
Boer W.D., “AMLCD Electronics”, Active Matrix Liquid Crystal Displays: Fundamentals and Applications, 2005 pp. 87-111, XP055089329, U.S.A, ISBN: 978-0-75-067813-1.
Boer W.D., “Improvement of Image Quality in AMLCDs”, Active Matrix Liquid Crystal Displays: Fundamentals and Applications, 2005, pp. 139-177, XP055089313, U.S.A, ISBN: 978-0-75-067813-1.
“Low Temperature Polysilicon TFT Reflective Color LCD” by Techno World, Feb. 18, 1999.
Microchem “Nano SU 8 2000”, product brochure for thick polymer, Rev. Feb. 2002.
“Microprism Technology for Liminaires,” Reflexite Corporation, Technical Publication RLO-181, Rev. 2 (2003).
Uchida T. et al., “Encyclopedia of Flat Panel Displays”, Japan, Kogyo Chosakai Publishing Co., Ltd./Yukio Shimura, Dec. 25, 2001, pp. 617 to 619.
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20110164067 A1 Jul 2011 US