Patent Grant
8346048
1. Field of the Invention
The present invention relates to microelectromechanical systems (MEMS).
2. Description of the Related Art
Microelectromechanical systems (MEMS) include micro mechanical elements, actuators, and electronics. Micromechanical elements may be created using deposition, etching, and/or other micromachining processes that etch away parts of substrates and/or deposited material layers or that add layers to form electrical and electromechanical devices. One type of MEMS device is called an interferometric modulator. As used herein, the term interferometric modulator or interferometric light modulator refers to a device that selectively absorbs and/or reflects light using the principles of optical interference. In certain embodiments, an interferometric modulator may comprise a pair of conductive plates, one or both of which may be transparent and/or reflective in whole or part and capable of relative motion upon application of an appropriate electrical signal. In a particular embodiment, one plate may comprise a stationary layer deposited on a substrate and the other plate may comprise a metallic membrane separated from the stationary layer by an air gap. As described herein in more detail, the position of one plate in relation to another can change the optical interference of light incident on the interferometric modulator. Such devices have a wide range of applications, and it would be beneficial in the art to utilize and/or modify the characteristics of these types of devices so that their features can be exploited in improving existing products and creating new products that have not yet been developed.
In one embodiment, an illumination device comprises a light guide having a first end for receiving light and configured to support propagation of light along the length of the light guide. A turning microstructure is disposed on a first side of the light guide configured to turn light incident on the first side and to direct the light out a second opposite side of the light guide, wherein the turning microstructure comprises a plurality of indentations. A cover is physically coupled to the light guide and disposed over the turning microstructure. An interlayer is between the cover and the light guide, wherein the interlayer physically couples the cover to the light guide. A plurality of open regions is between the interlayer and the plurality of indentations, wherein the light guide has a first index of refraction and the interlayer has a second index of refraction and the second index of refraction is lower than the first index of refraction.
In another embodiment, an illumination device comprises a light guide having a first end for receiving light and configured to support propagation of light along the length of the light guide. A turning microstructure is disposed on a first side of the light guide configured to turn light incident on the first side and to direct the light out a second opposite side of the light guide, wherein the turning microstructure comprises a plurality of indentations. A cover is physically coupled to the light guide and disposed over the turning microstructure. An interlayer is between the cover and the light guide, wherein the interlayer physically couples the cover to the light guide. A plurality of regions is between the interlayer and the plurality of indentations at least partially comprising a material different from the interlayer.
In another embodiment, an illumination device comprises a light guide having a first end for receiving light and configured to support propagation of light along the length of the light guide. A turning microstructure is disposed on a first side of the light guide configured to turn light incident on the first side and to direct the light out a second opposite side of the light guide, wherein the turning microstructure comprises a plurality of indentations. A cover is physically coupled to the light guide and disposed over the turning microstructure. A plurality of open regions is between the cover and the plurality of indentations, wherein the light guide has a first index of refraction and the cover has a second index of refraction and the second index of refraction is lower than the first index of refraction.
In another embodiment, a method of manufacturing a illumination device comprises providing a light guide having a first end for receiving light and configured to support propagation of light along the length of the light guide, said light guide having turning microstructure disposed on a first side thereof that is configured to turn light incident on the first side and to direct the light out a second opposite side of the light guide, wherein the turning microstructure comprises a plurality of indentations. The method also comprises providing a cover disposed over the turning microstructure. The method also comprises physically coupling the cover to the light guide by an interlayer such that a plurality of open regions are between the interlayer and the plurality of indentations, wherein the light guide has a first index of refraction and the interlayer has a second index of refraction and the second index of refraction is lower than the first index of refraction.
In another embodiment, a method of manufacturing a illumination device comprises providing a light guide having a first end for receiving light and configured to support propagation of light along the length of the light guide, said light guide having turning microstructure disposed on a first side thereof that is configured to turn light incident on the first side and to direct the light out a second opposite side of the light guide, wherein the turning microstructure comprises a plurality of indentations. The method also comprises providing a cover disposed over the turning microstructure. The method also comprises physically coupling the cover to the light guide by an interlayer such that a plurality of regions between the interlayer and the plurality of indentations at least partially comprises a material different from the interlayer.
In another embodiment, a method of manufacturing a illumination device comprises providing a light guide having a first end for receiving light and configured to support propagation of light along the length of the light guide, said light guide having turning microstructure disposed on a first side thereof that is configured to turn light incident on the first side and to direct the light out a second opposite side of the light guide, wherein the turning microstructure comprises a plurality of indentations. The method also comprises physically coupling a cover to the light guide, wherein the cover is disposed over the turning microstructure, and wherein the light guide has a first index of refraction and the cover has a second index of refraction and the second index of refraction is lower than the first index of refraction.
In another embodiment, an illumination device comprises a means for turning light having a first end for receiving light and configured to support propagation of light along the length of the light guiding means. A means for turning light is disposed on a first side of the light guiding means configured to turn light incident on the first side and to direct the light out a second opposite side of the light guiding means, wherein the turning means comprises a plurality of means for reflecting light. A means for covering is physically coupled to the light guiding means and disposed over the turning means. The device comprises a means for physically coupling the covering means to the light guiding means. A plurality of open regions are between the covering means and the plurality of reflecting means, wherein the light guiding means has a first index of refraction and the coupling means has a second index of refraction and the second index of refraction is lower than the first index of refraction.
In another embodiment, an illumination device comprises a means for turning light having a first end for receiving light and configured to support propagation of light along the length of the light guiding means. A means for turning light is disposed on a first side of the light guiding means configured to turn light incident on the first side and to direct the light out a second opposite side of the light guiding means, wherein the turning means comprises a plurality of means for reflecting light. A means for covering is physically coupled to the light guiding means and disposed over the turning means. The device comprises a means for physically coupling the covering means to the light guiding means. A plurality of regions are between the covering means and the plurality of reflecting means at least partially comprising a material different from the coupling means.
In another embodiment, an illumination device comprises a means for turning light having a first end for receiving light and configured to support propagation of light along the length of the light guiding means. A means for turning light is disposed on a first side of the light guiding means configured to turn light incident on the first side and to direct the light out a second opposite side of the light guiding means, wherein the turning means comprises a plurality of means for reflecting light. A means for covering is physically coupled to the light guiding means and disposed over the turning means. A plurality of open regions are between the covering means and the plurality of reflecting means, wherein the light guiding means has a first index of refraction and the covering means has a second index of refraction and the second index of refraction is lower than the first index of refraction.
The following detailed description is directed to certain specific embodiments of the invention. However, the invention can be embodied in a multitude of different ways. In this description, reference is made to the drawings wherein like parts are designated with like numerals throughout. As will be apparent from the following description, the embodiments may be implemented in any device that is configured to display an image, whether in motion (e.g., video) or stationary (e.g., still image), and whether textual or pictorial. More particularly, it is contemplated that the embodiments may be implemented in or associated with a variety of electronic devices such as, but not limited to, mobile telephones, wireless devices, personal data assistants (PDAs), hand-held or portable computers, GPS receivers/navigators, cameras, MP3 players, camcorders, game consoles, wrist watches, clocks, calculators, television monitors, flat panel displays, computer monitors, auto displays (e.g., odometer display, etc.), cockpit controls and/or displays, display of camera views (e.g., display of a rear view camera in a vehicle), electronic photographs, electronic billboards or signs, projectors, architectural structures, packaging, and aesthetic structures (e.g., display of images on a piece of jewelry). MEMS devices of similar structure to those described herein can also be used in non-display applications such as in electronic switching devices.
Certain embodiments included herein comprise illumination apparatus for displays. An illumination device may comprise a light guide having a first end for receiving light and configured to support propagation of light along the length of the light guide. A turning microstructure is disposed on a first side of the light guide configured to turn light incident on the first side and to direct the light out a second opposite side of the light guide, wherein the turning microstructure comprises a plurality of indentations. A cover is physically coupled to the light guide and disposed over the turning microstructure. A plurality of open regions is between the cover and the plurality of indentations. Various embodiments include methods of bonding the cover to the light guide while not filling the open regions between the cover and plurality of indentations (e.g., with adhesive).
One interferometric modulator display embodiment comprising an interferometric MEMS display element is illustrated in
The depicted portion of the pixel array in
The optical stacks 16a and 16b (collectively referred to as optical stack 16), as referenced herein, typically comprise several fused layers, which can include an electrode layer, such as indium tin oxide (ITO), a partially reflective layer, such as chromium, and a transparent dielectric. The optical stack 16 is thus electrically conductive, partially transparent, and partially reflective, and may be fabricated, for example, by depositing one or more of the above layers onto a transparent substrate 20. The partially reflective layer can be formed from a variety of materials that are partially reflective such as various metals, semiconductors, and dielectrics. The partially reflective layer can be formed of one or more layers of materials, and each of the layers can be formed of a single material or a combination of materials.
In some embodiments, the layers of the optical stack 16 are patterned into parallel strips, and may form row electrodes in a display device as described further below. The movable reflective layers 14a, 14b may be formed as a series of parallel strips of a deposited metal layer or layers (orthogonal to the row electrodes of 16a, 16b) deposited on top of posts 18 and an intervening sacrificial material deposited between the posts 18. When the sacrificial material is etched away, the movable reflective layers 14a, 14b are separated from the optical stacks 16a, 16b by a defined gap 19. A highly conductive and reflective material such as aluminum may be used for the reflective layers 14, and these strips may form column electrodes in a display device.
With no applied voltage, the gap 19 remains between the movable reflective layer 14a and optical stack 16a, with the movable reflective layer 14a in a mechanically relaxed state, as illustrated by the pixel 12a in
In one embodiment, the processor 21 is also configured to communicate with an array driver 22. In one embodiment, the array driver 22 includes a row driver circuit 24 and a column driver circuit 26 that provide signals to a display array or panel 30. The cross section of the array illustrated in
In typical applications, a display frame may be created by asserting the set of column electrodes in accordance with the desired set of actuated pixels in the first row. A row pulse is then applied to the row 1 electrode, actuating the pixels corresponding to the asserted column lines. The asserted set of column electrodes is then changed to correspond to the desired set of actuated pixels in the second row. A pulse is then applied to the row 2 electrode, actuating the appropriate pixels in row 2 in accordance with the asserted column electrodes. The row 1 pixels are unaffected by the row 2 pulse, and remain in the state they were set to during the row 1 pulse. This may be repeated for the entire series of rows in a sequential fashion to produce the frame. Generally, the frames are refreshed and/or updated with new display data by continually repeating this process at some desired number of frames per second. A wide variety of protocols for driving row and column electrodes of pixel arrays to produce display frames are also well known and may be used in conjunction with the present invention.
In the
The display device 40 includes a housing 41, a display 30, an antenna 43, a speaker 45, an input device 48, and a microphone 46. The housing 41 is generally formed from any of a variety of manufacturing processes as are well known to those of skill in the art, including injection molding and vacuum forming. In addition, the housing 41 may be made from any of a variety of materials, including, but not limited to, plastic, metal, glass, rubber, and ceramic, or a combination thereof In one embodiment, the housing 41 includes removable portions (not shown) that may be interchanged with other removable portions of different color, or containing different logos, pictures, or symbols.
The display 30 of exemplary display device 40 may be any of a variety of displays, including a bi-stable display, as described herein. In other embodiments, the display 30 includes a flat-panel display, such as plasma, EL, OLED, STN LCD, or TFT LCD as described above, or a non-flat-panel display, such as a CRT or other tube device, as is well known to those of skill in the art. However, for purposes of describing the present embodiment, the display 30 includes an interferometric modulator display, as described herein.
The components of one embodiment of exemplary display device 40 are schematically illustrated in
The network interface 27 includes the antenna 43 and the transceiver 47 so that the exemplary display device 40 can communicate with one or more devices over a network. In one embodiment, the network interface 27 may also have some processing capabilities to relieve requirements of the processor 21. The antenna 43 is any antenna known to those of skill in the art for transmitting and receiving signals. In one embodiment, the antenna transmits and receives RF signals according to the IEEE 802.11 standard, including IEEE 802.11(a), (b), or (g). In another embodiment, the antenna transmits and receives RF signals according to the BLUETOOTH standard. In the case of a cellular telephone, the antenna is designed to receive CDMA, GSM, AMPS, or other known signals that are used to communicate within a wireless cell phone network. The transceiver 47 pre-processes the signals received from the antenna 43 so that they may be received by and further manipulated by the processor 21. The transceiver 47 also processes signals received from the processor 21 so that they may be transmitted from the exemplary display device 40 via the antenna 43.
In an alternative embodiment, the transceiver 47 can be replaced by a receiver. In yet another alternative embodiment, network interface 27 can be replaced by an image source, which can store or generate image data to be sent to the processor 21. For example, the image source can be a digital video disc (DVD) or a hard-disc drive that contains image data, or a software module that generates image data.
Processor 21 generally controls the overall operation of the exemplary display device 40. The processor 21 receives data, such as compressed image data from the network interface 27 or an image source, and processes the data into raw image data or into a format that is readily processed into raw image data. The processor 21 then sends the processed data to the driver controller 29 or to frame buffer 28 for storage. Raw data typically refers to the information that identifies the image characteristics at each location within an image. For example, such image characteristics can include color, saturation, and gray-scale level.
In one embodiment, the processor 21 includes a microcontroller, CPU, or logic unit to control operation of the exemplary display device 40. Conditioning hardware 52 generally includes amplifiers and filters for transmitting signals to the speaker 45, and for receiving signals from the microphone 46. Conditioning hardware 52 may be discrete components within the exemplary display device 40, or may be incorporated within the processor 21 or other components.
The driver controller 29 takes the raw image data generated by the processor 21 either directly from the processor 21 or from the frame buffer 28 and reformats the raw image data appropriately for high speed transmission to the array driver 22. Specifically, the driver controller 29 reformats the raw image data into a data flow having a raster-like format, such that it has a time order suitable for scanning across the display array 30. Then the driver controller 29 sends the formatted information to the array driver 22. Although a driver controller 29, such as a LCD controller, is often associated with the system processor 21 as a stand-alone Integrated Circuit (IC), such controllers may be implemented in many ways. They may be embedded in the processor 21 as hardware, embedded in the processor 21 as software, or fully integrated in hardware with the array driver 22.
Typically, the array driver 22 receives the formatted information from the driver controller 29 and reformats the video data into a parallel set of waveforms that are applied many times per second to the hundreds and sometimes thousands of leads coming from the display's x-y matrix of pixels.
In one embodiment, the driver controller 29, array driver 22, and display array 30 are appropriate for any of the types of displays described herein. For example, in one embodiment, driver controller 29 is a conventional display controller or a bi-stable display controller (e.g., an interferometric modulator controller). In another embodiment, array driver 22 is a conventional driver or a bi-stable display driver (e.g., an interferometric modulator display). In one embodiment, a driver controller 29 is integrated with the array driver 22. Such an embodiment is common in highly integrated systems such as cellular phones, watches, and other small area displays. In yet another embodiment, display array 30 is a typical display array or a bi-stable display array (e.g., a display including an array of interferometric modulators).
The input device 48 allows a user to control the operation of the exemplary display device 40. In one embodiment, input device 48 includes a keypad, such as a QWERTY keyboard or a telephone keypad, a button, a switch, a touch-sensitive screen, or a pressure- or heat-sensitive membrane. In one embodiment, the microphone 46 is an input device for the exemplary display device 40. When the microphone 46 is used to input data to the device, voice commands may be provided by a user for controlling operations of the exemplary display device 40.
Power supply 50 can include a variety of energy storage devices as are well known in the art. For example, in one embodiment, power supply 50 is a rechargeable battery, such as a nickel-cadmium battery or a lithium ion battery. In another embodiment, power supply 50 is a renewable energy source, a capacitor, or a solar cell including a plastic solar cell, and solar-cell paint. In another embodiment, power supply 50 is configured to receive power from a wall outlet.
In some embodiments, control programmability resides, as described above, in a driver controller which can be located in several places in the electronic display system. In some embodiments, control programmability resides in the array driver 22. Those of skill in the art will recognize that the above-described optimizations may be implemented in any number of hardware and/or software components and in various configurations.
The details of the structure of interferometric modulators that operate in accordance with the principles set forth above may vary widely. For example,
In embodiments such as those shown in
As described above, light incident on an interferometric modulator is either reflected or absorbed via constructive or destructive interference according to an actuation state of one of the reflective surfaces. An illumination apparatus may provide artificial lighting to a display device comprising an interferometric modulator or array thereof.
In some embodiments, an illumination system comprises a light source, a light injection system, and a light guide panel that includes a light “turning” film. The light injection system transforms light from a point source (e.g., a light emitting diode (LED)) into a line source. A light bar having turning features may be used for this purpose. Light injected into the light bar propagates along the length of the bar and is ejected out of the bar over the length of the bar. This light is then spread across a wide area and directed onto an array of display elements. A light guide panel also having turning features thereon may be used for this purpose. The light ejected from the light bar is coupled into an edge of the light guide panel and propagated within the light guide panel. Turning features eject the light from the panel over an area corresponding the plurality of display elements.
The turning microstructure 82 of the light guide 80 comprises a plurality of turning features or indentations 82a having facets or sloping surfaces configured to direct light out the second side 80b of the light guide 80. In certain embodiments, the turning features may comprise a plurality of surface features or volume features. In some embodiments, the turning microstructure 82a comprises a diffractive optical element. The diffractive optical element may comprise volume or surface features extending across the length of the turning microstructure 82. In certain embodiments, the turning microstructure 82 comprises a hologram and the turning features comprise holographic features. The hologram may comprise holographic volume or surface features, extending across the length of the turning microstructure 82. The size, shape, and separation of the turning features may vary. A wide variety of other types of turning features, diffractive, holographic, prismatic, or otherwise are possible. Accordingly, different sizes, shapes, configuration, and arrangements may be employed.
The features 82a shown in
In the embodiment illustrated in
A light source 84 comprising, for example, one or more light emitting diodes (LEDs) is disposed with respect to the light guide 80 to inject light therein. In the embodiment shown in
The turning microstructure 82 and/or light guide region 80 typically comprises a material such as glass, polycarbonate, acrylic such as polymethymethacrylate (PMMA), acrylate copolymers such as poly(styrene-methylmethacrylate) polymers (PS-PMMA, sold under the name of Zylar), UV-curable resins, or other optically transparent materials. The index of refraction of polycarbonate is approximately 1.59 and for Zylar is approximately 1.54 for wavelengths in the visible spectrum. According to some embodiments, the light guide 80 may be a single layer, such as a plastic or glass, with facets formed on the top surface. The facets can be formed, for example, by embossing or etching directly onto the plastic or glass substrate. According to other embodiments, the light guide 80 may include a plurality of layers over a substrate that is glass or plastic, such as polycarbonate, PET, etc. In these embodiments, the turning microstructure may be formed on a turning film over the substrate, such a UV-embossed resin, or an inorganic coating etched to various shapes. The turning film could be chosen to have the same index of refraction as the substrate to form one optical body for the light guide 80.
In other embodiments, one or more additional optical layers, such as an optical isolation layer may be disposed on the substrate of the display panel 81, or display elements or interferometric modulators, to otherwise improve the optical performance of the display. For example, an optical isolation layer 85 may be provided between the light guiding portion 80 of the display and the interferometric modulators 81 to prevent the interferometric modulators from absorbing light propagating through the light guiding portion.
For example, the interferometric modulators are typically absorptive structures for light rays guided at an angle of 45-90 degrees measured from the normal to the display elements. Thus, some of the light propagating through the light guide 80 and incident on the interferometric modulators 81 at an oblique angle may be substantially absorbed by the interferometric modulators 81 after a sufficient number of reflections. In order to reduce, minimize, or prevent this loss of light due to absorption, the optical isolation layer 85 may be disposed between the light guide region 80 and the interferometric modulators. According to some embodiments, the optical isolation layer 85 advantageously has an index of refraction substantially lower than the light guide region 80, such that light traveling through the light guide 80 and striking the optical isolation film interface at an oblique or grazing angle, for example, greater than the critical angle (e.g., greater than 50° or 60°), will be totally internally reflected back into the light guiding region 80. In various embodiments, the optical isolation layer 85 comprises silicon dioxide, or fluorinated silicon dioxide. Other materials may be employed as well. As described herein, the geometric arrangement of the turning microstructure 82, and additional optical films on the substrate relative to the interferometric modulators may be selected to enhance the efficiency of the light guiding portion of the display, to further enhance the optical performance of the overall display, or provide other advantages.
The plurality of display elements 81 may be formed using any of a variety of manufacturing processes known to those skilled in the art to adhere one or more of the optical layers described herein on the glass or plastic substrate supporting the array of display elements. The glass or plastic substrate comprises a support layer upon which the display elements, such as an array of interferometric modulators, are fabricated. As disclosed herein, the substrate may be further used to support one or more optical layers of the display device.
In certain embodiments, the light guide 80 may comprise more than one layer. For such embodiments, the indices of refraction of the multiple optical layers comprising the light guiding portion 80 may in some embodiments advantageously be close such that light may be transmitted through the multiple optical layers without being substantially reflected or refracted. The light guide 80 may for example have an index of refraction of 1.52. As described above, the light guide 80 may comprise glass or polymeric material in certain embodiments.
The material of the cover layer 90 facilitates guiding of light within the light guide region 80 via total internal reflection. In particular, in various embodiments the portion of the cover layer 90 immediately adjacent to the lightguide 80 has an index of refraction smaller than that of the light guide 80. Since the index of refraction of the light guide 80 is greater than that of cover layer 90, light incident on the interface of the light guide 80 and the cover layer 90 at an angle greater than the critical angle will be reflected back into the light guiding region 80 and will continue to propagate along the light guiding region 80. Thus, light that is injected into the edge of light guide 80 is propagated along its length at least in part through total internal reflection due to the difference in index of refraction between the light guide 80 and the cover layer 90.
In various embodiments, the cover layer 90 is adhered to the light guide 80 such that the turning microstructure 82 is between the cover layer 90 and the light guide 80. The cover layer 90 may be adhered, laminated, pressed, fused etc., onto the light guide 80, or another layer between the cover layer 90 and the light guide 80, in a variety of ways. In certain embodiments of the invention, cover layer 90 is adhered to light guide 80 such that the plurality of open regions 91 is preserved. According to some embodiments, the open regions 91 are substantially filled with air and provide a difference in refractive index from the light guide 80 such that much of the light incident on the turning features 82a is turned and redirected towards the plurality of display elements 85. The interface between the light guide material and air provides total internal reflection for light incident on the interface at angles greater than the critical angle.
In some embodiments, the cover layer 90 may make direct contact with the light guide 80, and in particular embodiments, the cover layer 90 may make contact for over about 90% or more of the surface area of the first side 80a of the light guide 80, for example, on the elevated surfaces 82b of the light guide 80 between the facets 82a. In other embodiments, the cover layer 90 does not directly contact the light guide 80 but is attached by an intervening adhesive layer.
In some embodiments in which the cover layer 90 directly contacts the light guide 80, adhesion can be performed by ultrasonic or thermal bonding between the surface of cover layer 90 and the elevated surfaces 82b of light guide 80. In the case of thermal bonding, which involves the use of heat to bond two surfaces together, the surface of the light guide 80 and/or turning microstructure 82 can comprise cross-linked polymers and can initially be cured with UV light. The turning microstructure 82 may first be formed by UV-embossing, which typically involves replicating from a mold UV-curable epoxy on a substrate. This process of UV-embossing the turning microstructure 82 prior to adhering a cover film 90 to the elevated surfaces 82b of the microstructure 82 can prevent or reduce the likelihood that the surfaces of the light guide 80 and/or turning microstructure 82 melts during thermal bonding, and can thus help maintain their shape and light turning optical function.
According to another embodiment, the cover layer 90 may be directly adhered to light guide 80 by a preparation process that includes activating either the surface of cover film 90 or the surfaces of light guide 80 (e.g. turning microstructure 82), or both, with a plasma to improve adhesion, and subsequent UV radiation. For example, an oxygen plasma can be used to prepare the polymer surface, by first removing weak surface layers with the lowest molecular weight, while oxidizing the uppermost atomic layers of the polymer. UV radiation can be applied to promote formation of oxygen radicals, which can help break bonds and promote the cross linking of surface molecules. The consequent oxidation of the polymer causes an increase in polar groups, which enhances adhesion properties of the two polymer surfaces during the actual bonding step.
According to certain embodiments, the interlayer 94 has very low surface energy. For example, interlayer 94 can be a self-wetting adhesive. According to some embodiments, the interlayer 94 can have a surface tension of less than 35 dynes/cm. According to other embodiments, the interlayer 94 can have a surface tension of less than 25 dynes/cm. A self-wetting interlayer 94 can be applied or coated over a surface of the cover layer 90, and the cover layer 90 with the self-wetting interlayer 94 can be placed over the light guide 80 and turning microstructure 82. Simple pressure can be applied over the cover layer 90 to bond the surface of the interlayer 94 and surface of the light guide 80, due to the low surface energy of the interlayer. In some cases, a support frame placed over the cover layer 90 and the light guide 80 may be useful to provide the pressure for self-wetting to occur.
According to certain embodiments, the interlayer 94 is a polymer material with a low glass transition point (Tg) that is elastically deformable, such as a rubber or elastomeric gel-like material. The elastomeric properties can preserve the regions within the grooves 82a of the turning microstructure 82 by providing for reversal of any material ingress into the grooves 82a when the external force causing initial deformation is removed. In other words, the interlayer 94 is sufficiently elastically deformable as to avoid plastic flow into the grooves 82a upon external pressure, e.g., from accidental impact during device operation, that would prevent total internal reflection. The amount of cross linking could be increased to strengthen or rigidify the polymer, where desired, and render it less sensitive to temperature changes. According to certain embodiments, the polymer material comprises an elastomer material, such as silicone, polypropylene, or poly-isobutylene. According to certain embodiments, the interlayer comprises a siloxane backbone, including but not limited to polydimethyl siloxane, polydiethyl siloxane, polymethylphenyl siloxane, etc. According to some embodiments, the interlayer comprises a silicone elastomer. According to some embodiments, the interlayer comprises fluoropolymers, polypropylene and other amorphous hydrocarbon polymers with low surface energy to provide an optical bond with the light guide, and a refractive index lower than that of the rest of the light guide.
According to certain embodiments, the interlayer can comprises a polymer material with a Tg that is lower than most operating temperatures and maintains its adhesive or elastomeric properties under most environmental conditions. For example, the low Tg material can have a Tg that is lower than 25° C., 0° C., −20° C., −40° C., etc. According to certain embodiments, the polymer material has a glass transition temperature below about 300° C. According to other embodiments, the polymer material has a glass transition temperature below about 200° C. According to other embodiments, the polymer material has a glass transition temperature below about 0° C.
According to some embodiments, the interlayer has an index of refraction that is sufficiently lower than that of the light guide to provide for total internal reflection. According to some embodiments, the interlayer has a sufficiently low surface energy to physically couple the cover to areas of the turning microstructure between the grooves. According to some embodiments, the interlayer has sufficiently elastomeric properties to preserve open regions in the turning microstructure and preserve total internal reflection. In some embodiments, the interlayer does not fill at least 50%, 60%, 70%, 80%, or 90% of the grooves, indentations or turning microstructure disposed across the light guide. Additionally, according to some embodiments, the interlayer does not fill substantially all of the region within the groove of the turning microstructure. For example, according to some embodiments, on average, the interlayer does not fill at least 50%, 60%, 70%, 80%, or 90% of the region within the grooves or turning microstructure. According to some embodiments, the interlayer has an index of refraction that is sufficiently lower than that of the light guide to provide for total internal reflection, a sufficiently low surface energy to physically couple the cover to areas of the turning microstructure between the grooves, and sufficiently elastomeric properties to preserve open regions in the turning microstructure and preserve total internal reflection.
According to certain embodiments, the thickness of the interlayer 94 is less than the height of the indentation of the turning microstructure. According to certain embodiments, the thickness of the interlayer 94 is less than ½, ¼, ⅛, 1/10, etc., the height of the indentations. For example, if an indentation of the turning microstructure is about 2 microns tall, the interlayer thickness can be about 200 nm thick. According to some embodiments, the thickness of the interlayer 94 can be 10 microns or more, 20 microns or more, 50 microns or more, or 100 microns or more.
Such an adhesive layer can be formed by conventional wet coating processes, such as spin, spray, dip, roll, inkjet, etc., which can typically form very thin films by employing dilute solutions of the coating material. After a very thin adhesive layer is formed on cover layer 90, the cover layer 90 with the thin adhesive can be placed over the light guide 80 with the application of pressure and temperature to provide contact with surfaces 82b of turning microstructure 82. The thin adhesive can then be cured with UV light or heat to bond the surface of cover layer 90 with surfaces of the turning microstructure 82.
In various embodiments, the films are made to be very thin to reduce or minimize the risk of excess adhesive material filling the grooves of the turning microstructure 82 after lamination of the adhesive material on the cover layer 90. Reducing or minimizing thickness of the adhesive material would keep the regions 91 within the grooves or indentations 82a open, and the optical performance of the display device optimized. Light over a wider range of angle total internally reflects if air having an index of 1.0 is within the indentation. Moreover, even if the filling of some adhesive material in the grooves 82a of the turning microstructure 82 occurs, the size of the grooves and amount of adhesive material can be configured such that the amount of adhesive material that falls into the grooves 82a may reduce the size of the open regions 91, without entirely filling the regions. Partial filling of the grooves 82a may decrease the likelihood that the grooves are visible to a viewer and/or may be factored into the design of the illumination system (e.g., in the selection of groove width).
For the embodiment of a very thin adhesive film, it can be advantageous that the adhesive material shows sufficient mechanical compliance so that optical contact can be increased or maximized. According to some embodiments, the adhesive material comprises a polymer material having a low glass transition point and is thus gel-like and deformable, but also having a high viscosity, or highly cross-linked networks. Preferably, the adhesive material comprises a soft polymer material that can conform easily to another surface, particularly a surface that has been UV-cured and is less compliant, and thus the adhesive material has a low molecular weight in various embodiments. Examples include acrylic pre-polymer mixtures, which have high viscosities, including for example polymethymethacrylate (PMMA), and poly(styrene-methylmethacrylate) (PS-PMMA), and other acrylic polymers. Other examples include polymer formulations typically used as pressure sensitive adhesives.
According to some embodiments, the index of refraction of the adhesive layer 94, which directly overlies the turning microstructure 83, has a lower index of refraction than that of the light guide 80 so that total internal reflection can occur within the light guide 80.
According to certain embodiments of a thicker adhesive, the thickness can be equal to or larger than the size of a feature 82a in the turning microstructure 82, and can range for example, from about 0.5 micron to about 50 microns in thickness. Since there is enough adhesive material to fill the grooves of the turning microstructure in this case, the adhesive material may be cured such that it does not flow or plastically deform when attaching the cover 90 to the light guide 80, in order to avoid the filling of grooves 82a with adhesive material during lamination. The process of forming a thicker adhesive is similar to the process of forming a thin adhesive as set forth above. However, the adhesive mixture in the embodiment of the thicker adhesive can be additionally cured to further reduce or minimize the flowability of the thick adhesive material. According to some embodiments, a thick adhesive material, such as a polymer material, is first coated onto or deposited over a cover layer 90. The thick adhesive material can be pre-cured to partially cross-link the polymer chains, and stop the flow of the adhesive. The cover layer with the thick adhesive can then be placed over the light guide panel 80 with the application of pressure and temperature to provide optical contact. The thick adhesive can then be cured a second time with UV light or heat to complete partial cross-linking and seal the surface of cover layer 90 with surfaces of the light guide 80. The pre-curing step helps avoid the filling or partial filling of grooves 82a of the turning microstructrure 82 with the thick adhesive material.
According to some embodiments, the adhesive materials comprise polymer materials with low glass transition points, highly cross-linked networked materials, or gel-like structures. According to some embodiments, the adhesive materials comprise silicones such as polydimethyl siloxanes, polydiethyl siloxanes, polymethylphenyl siloxanes, or acrylates with hydrocarbon side chains, such as t-butyl acrylate, or polyester materials, such as polytetramethylene ether glycol. Some embodiments provide the opportunity to further cross-link and fortify the adhesive, such as by including additional cross-linking density. As discussed above, the index of refraction of the thicker adhesive layer is lower than that of the light guide 80 in some embodiments. Moreover, the thicker adhesive can provide additional functionalities, such as optical diffusion, color filtering, mechanical shock absorption, etc.
According to another embodiment, the cover layer 90 can be solvent-welded, which includes exposing a surface of a cover layer 90 to a solvent that is chemically soluble with the surfaces of the cover layer 90 and of the light guide 80. The cover layer 90 with the solvent applied over a surface may be placed over the light guide 80. In some embodiments, application of pressure and temperature can increase optical contact and provides for inter-diffusion between the surface of the cover layer 90 and surfaces in areas 82b between the grooves. In certain embodiments, the light guide 80 can comprise a material that is cross-linked and UV-cured so that the solvent does not dissolve the features 82a of the turning microstructure 82.
According to various embodiments, the solvent comprises a liquid solvent. According to certain embodiments, the solvent comprises a polymerizable mixture. The polymerizable mixture may comprise a monomer and an initiator, unless the monomer itself can self-initiate. According to some embodiments, a solvent may further comprise molecular coupling agents, including tri-functional amino silanes (e.g., amino propyl tri-ethoxy silane), which activates the surfaces for bonding during lamination of the cover layer 90 to the light guide 80 and improves the seal between surfaces. An advantage of adding a molecular coupling agent, such as certain amino silanes, to a solvent applied to a cover layer 90 is that the amino groups of the molecular coupling agent, such as NH2 groups, can more easily react with the material of the light guide 80. For example, a silane-based coupling agent may bond readily with surface hydroxyl groups of the light guide 80, and render the surface of the light guide 80 more active towards bonding with cover layer 90. Other coupling agents as known in the art, including various silicates and titanates, can accordingly be used to increase the interfacial bonds between the surfaces of the cover and the light guide 80.
According to certain embodiments, the open regions 82a can be filled with air. However, according to other embodiments as shown in
According to some embodiments, as shown in
According to another embodiment (not shown), the turning microstructure can comprise binary gratings as shown in
The turning microstructures according to some embodiments can be formed by the process shown in
A wide variety of variations are possible. Films, layers, components, and/or elements may be added, removed, or rearranged. Additionally, processing steps may be added, removed, or reordered. Also, although the terms “film” and “layer” have been used herein, such terms as used herein may include film stacks and multilayers. Such film stacks and multilayers may be adhered to other structures using adhesive or may be formed on other structures using deposition or in other manners.
Moreover, although this invention has been disclosed in the context of certain preferred embodiments and examples, it will be understood by those skilled in the art that the present invention extends beyond the specifically disclosed embodiments to other alternative embodiments and/or uses of the invention and obvious modifications and equivalents thereof In addition, while several variations of the invention have been shown and described in detail, other modifications, which are within the scope of this invention, will be readily apparent to those of skill in the art based upon this disclosure. It is also contemplated that various combinations or sub-combinations of the specific features and aspects of the embodiments may be made and still fall within the scope of the invention. It should be understood that various features and aspects of the disclosed embodiments can be combined with, or substituted for, one another in order to form varying modes of the disclosed invention. Thus, it is intended that the scope of the present invention herein disclosed should not be limited by the particular disclosed embodiments described above, but should be determined only by a fair reading of the claims that follow.
The present application claims priority to U.S. Provisional Application No. 61/056,601, filed May 28, 2008, the disclosure of which is hereby incorporated by reference herein in its entirety.
| Number | Name | Date | Kind |
|---|---|---|---|
| 4375312 | Tangonan | Mar 1983 | A |
| 4378567 | Mir | Mar 1983 | A |
| 4974942 | Gross | Dec 1990 | A |
| 5050946 | Hathaway | Sep 1991 | A |
| 5221982 | Faris | Jun 1993 | A |
| 5226099 | Mignardi et al. | Jul 1993 | A |
| 5339179 | Rudisill | Aug 1994 | A |
| 5341242 | Gilboa et al. | Aug 1994 | A |
| 5481385 | Zimmerman et al. | Jan 1996 | A |
| 5555160 | Tawara | Sep 1996 | A |
| 5592332 | Nishio | Jan 1997 | A |
| 5647036 | Deacon | Jul 1997 | A |
| 5671994 | Tai | Sep 1997 | A |
| 5703667 | Ochiai | Dec 1997 | A |
| 5712694 | Taira et al. | Jan 1998 | A |
| 5771321 | Stern | Jun 1998 | A |
| 5783614 | Chen | Jul 1998 | A |
| 5892598 | Asakawa et al. | Apr 1999 | A |
| 5914760 | Daiku | Jun 1999 | A |
| 6040937 | Miles | Mar 2000 | A |
| 6074069 | Chao-Ching | Jun 2000 | A |
| 6091469 | Naito | Jul 2000 | A |
| 6099134 | Taniguchi | Aug 2000 | A |
| 6123431 | Teragaki | Sep 2000 | A |
| 6195196 | Kimura | Feb 2001 | B1 |
| 6259854 | Shinji et al. | Jul 2001 | B1 |
| 6379017 | Nakabayashi et al. | Apr 2002 | B2 |
| 6407785 | Yamazaki | Jun 2002 | B1 |
| 6454452 | Sasagawa | Sep 2002 | B1 |
| 6512626 | Schmidt | Jan 2003 | B1 |
| 6522794 | Bischel | Feb 2003 | B1 |
| 6582095 | Toyoda | Jun 2003 | B1 |
| 6592234 | Epstein | Jul 2003 | B2 |
| 6603520 | Umemoto | Aug 2003 | B2 |
| 6631998 | Egawa et al. | Oct 2003 | B2 |
| 6636358 | Umemoto et al. | Oct 2003 | B2 |
| 6642913 | Kimura et al. | Nov 2003 | B1 |
| 6650455 | Miles | Nov 2003 | B2 |
| 6652109 | Nakamura | Nov 2003 | B2 |
| 6657683 | Richard | Dec 2003 | B2 |
| 6667782 | Taira et al. | Dec 2003 | B1 |
| 6669350 | Yamashita | Dec 2003 | B2 |
| 6674562 | Miles | Jan 2004 | B1 |
| 6685342 | Terada | Feb 2004 | B2 |
| 6693690 | Umemoto | Feb 2004 | B2 |
| 6709123 | Flohr | Mar 2004 | B2 |
| 6742921 | Umemoto | Jun 2004 | B2 |
| 6747801 | Umemoto et al. | Jun 2004 | B2 |
| 6751023 | Ariyoshi et al. | Jun 2004 | B2 |
| 6761461 | Mizutani et al. | Jul 2004 | B2 |
| 6773126 | Hatjasalo | Aug 2004 | B1 |
| 6778746 | Charlton | Aug 2004 | B2 |
| 6798469 | Kimura | Sep 2004 | B2 |
| 6819380 | Wen et al. | Nov 2004 | B2 |
| 6852396 | Mineo | Feb 2005 | B1 |
| 6862141 | Olczak | Mar 2005 | B2 |
| 6865312 | Niv et al. | Mar 2005 | B2 |
| 6879354 | Sawayama | Apr 2005 | B1 |
| 6883924 | Maeda et al. | Apr 2005 | B2 |
| 6891530 | Umemoto et al. | May 2005 | B2 |
| 6930816 | Mochizuki | Aug 2005 | B2 |
| 6964484 | Gupta | Nov 2005 | B2 |
| 6966685 | Li et al. | Nov 2005 | B2 |
| 7010212 | Emmons et al. | Mar 2006 | B2 |
| 7042643 | Miles | May 2006 | B2 |
| 7072096 | Holman et al. | Jul 2006 | B2 |
| 7110158 | Miles | Sep 2006 | B2 |
| 7123216 | Miles | Oct 2006 | B1 |
| 7133022 | Grabert | Nov 2006 | B2 |
| 7142347 | Islam | Nov 2006 | B2 |
| 7156546 | Higashiyama | Jan 2007 | B2 |
| 7186014 | Shimura | Mar 2007 | B2 |
| 7218812 | Maxwell | May 2007 | B2 |
| 7262754 | Yamazaki | Aug 2007 | B1 |
| 7278774 | Chang | Oct 2007 | B2 |
| 7327510 | Cummings et al. | Feb 2008 | B2 |
| 7352501 | Chopra et al. | Apr 2008 | B2 |
| 7355780 | Chui | Apr 2008 | B2 |
| 7359011 | Hamada | Apr 2008 | B2 |
| 7360939 | Sugiura | Apr 2008 | B2 |
| 7366393 | Cassarly | Apr 2008 | B2 |
| 7380969 | Yamashita | Jun 2008 | B2 |
| 7417784 | Sasagawa | Aug 2008 | B2 |
| 7450295 | Tung | Nov 2008 | B2 |
| 7452120 | Lee et al. | Nov 2008 | B2 |
| 7515336 | Lippey | Apr 2009 | B2 |
| 7532800 | Iimura | May 2009 | B2 |
| 7543974 | Bourdelais et al. | Jun 2009 | B2 |
| 7706050 | Sampsell | Apr 2010 | B2 |
| 7722790 | Krishnan et al. | May 2010 | B2 |
| 7733439 | Sampsell | Jun 2010 | B2 |
| 7750886 | Sampsell | Jul 2010 | B2 |
| 7766531 | Anderson et al. | Aug 2010 | B2 |
| 7777954 | Gruhlke | Aug 2010 | B2 |
| 7855827 | Xu et al. | Dec 2010 | B2 |
| 20010019479 | Nakabayashi | Sep 2001 | A1 |
| 20020051354 | Egawa | May 2002 | A1 |
| 20020106182 | Kawashima | Aug 2002 | A1 |
| 20020154256 | Gotoh | Oct 2002 | A1 |
| 20030030764 | Lee | Feb 2003 | A1 |
| 20030034445 | Boyd et al. | Feb 2003 | A1 |
| 20030071947 | Shiraogawa | Apr 2003 | A1 |
| 20030083429 | Smith | May 2003 | A1 |
| 20030086030 | Taniguchi et al. | May 2003 | A1 |
| 20030086031 | Taniguchi | May 2003 | A1 |
| 20030090887 | Igarashi | May 2003 | A1 |
| 20030095401 | Hanson | May 2003 | A1 |
| 20030099118 | Saitoh | May 2003 | A1 |
| 20030103344 | Niida | Jun 2003 | A1 |
| 20030123245 | Parker | Jul 2003 | A1 |
| 20030160919 | Suzuki | Aug 2003 | A1 |
| 20030165067 | Imamura | Sep 2003 | A1 |
| 20030169385 | Okuwaki | Sep 2003 | A1 |
| 20030184989 | Matsumoto et al. | Oct 2003 | A1 |
| 20030193630 | Chiou | Oct 2003 | A1 |
| 20030210222 | Ogiwara | Nov 2003 | A1 |
| 20030210367 | Nakano | Nov 2003 | A1 |
| 20030214728 | Olczak | Nov 2003 | A1 |
| 20040001169 | Saiki | Jan 2004 | A1 |
| 20040017599 | Yang | Jan 2004 | A1 |
| 20040027315 | Senda et al. | Feb 2004 | A1 |
| 20040070711 | Wen | Apr 2004 | A1 |
| 20040080938 | Holman | Apr 2004 | A1 |
| 20040109305 | Chisholm | Jun 2004 | A1 |
| 20040135494 | Miyatake | Jul 2004 | A1 |
| 20040188599 | Viktorovitch | Sep 2004 | A1 |
| 20040228109 | Leu | Nov 2004 | A1 |
| 20040228112 | Takata | Nov 2004 | A1 |
| 20050002175 | Matsui et al. | Jan 2005 | A1 |
| 20050018103 | Lubart et al. | Jan 2005 | A1 |
| 20050024849 | Parker | Feb 2005 | A1 |
| 20050024890 | Yamamoto | Feb 2005 | A1 |
| 20050041175 | Akiyama | Feb 2005 | A1 |
| 20050046011 | Chen | Mar 2005 | A1 |
| 20050069254 | Schultheis | Mar 2005 | A1 |
| 20050146897 | Mimura | Jul 2005 | A1 |
| 20050185416 | Lee et al. | Aug 2005 | A1 |
| 20050231981 | Hoelen et al. | Oct 2005 | A1 |
| 20050270798 | Lee et al. | Dec 2005 | A1 |
| 20050271325 | Anderson | Dec 2005 | A1 |
| 20060002141 | Ouderkirk | Jan 2006 | A1 |
| 20060002675 | Choi et al. | Jan 2006 | A1 |
| 20060061705 | Onishi | Mar 2006 | A1 |
| 20060066586 | Gally | Mar 2006 | A1 |
| 20060066935 | Cummings | Mar 2006 | A1 |
| 20060077123 | Gally | Apr 2006 | A1 |
| 20060110090 | Ellwood | May 2006 | A1 |
| 20060132383 | Gally | Jun 2006 | A1 |
| 20060164861 | Maeda | Jul 2006 | A1 |
| 20060187676 | Ishikura | Aug 2006 | A1 |
| 20060209012 | Hagood, IV | Sep 2006 | A1 |
| 20060209385 | Liu | Sep 2006 | A1 |
| 20060215958 | Yeo | Sep 2006 | A1 |
| 20060268574 | Jung | Nov 2006 | A1 |
| 20070097694 | Faase | May 2007 | A1 |
| 20070133226 | Mi | Jun 2007 | A1 |
| 20070147087 | Parker | Jun 2007 | A1 |
| 20070187852 | Parker et al. | Aug 2007 | A1 |
| 20070189036 | Chen | Aug 2007 | A1 |
| 20070201234 | Ottermann | Aug 2007 | A1 |
| 20070279727 | Gandhi | Dec 2007 | A1 |
| 20070292091 | Fujii | Dec 2007 | A1 |
| 20080089092 | Lee et al. | Apr 2008 | A1 |
| 20080090025 | Freking | Apr 2008 | A1 |
| 20080094853 | Kim | Apr 2008 | A1 |
| 20080100900 | Chui | May 2008 | A1 |
| 20080170414 | Wang | Jul 2008 | A1 |
| 20080232135 | Kinder | Sep 2008 | A1 |
| 20080285307 | Aylward | Nov 2008 | A1 |
| 20090015753 | Ye | Jan 2009 | A1 |
| 20090097100 | Gally | Apr 2009 | A1 |
| 20090126792 | Gruhlke | May 2009 | A1 |
| 20090135469 | Lee et al. | May 2009 | A1 |
| 20090147332 | Bita et al. | Jun 2009 | A1 |
| 20090147535 | Mienko | Jun 2009 | A1 |
| 20090168459 | Holman | Jul 2009 | A1 |
| 20090201571 | Gally | Aug 2009 | A1 |
| 20100026727 | Bita et al. | Feb 2010 | A1 |
| 20100039832 | Ahlgren et al. | Feb 2010 | A1 |
| 20100051089 | Khazeni | Mar 2010 | A1 |
| 20100053148 | Khazeni | Mar 2010 | A1 |
| 20100141557 | Gruhlke | Jun 2010 | A1 |
| 20100177533 | Griffiths | Jul 2010 | A1 |
| 20100231510 | Sampsell | Sep 2010 | A1 |
| 20100309687 | Sampsell | Dec 2010 | A1 |
| Number | Date | Country |
|---|---|---|
| 1381752 | Nov 2002 | CN |
| 1643439 | Jul 2005 | CN |
| 0 278 038 | Aug 1988 | EP |
| 0539099 | Apr 1993 | EP |
| 0 590 511 | Apr 1994 | EP |
| 0621500 | Oct 1994 | EP |
| 0 879 991 | Nov 1998 | EP |
| 0 957 392 | Nov 1999 | EP |
| 0 984 314 | Mar 2000 | EP |
| 1116987 | Jul 2001 | EP |
| 1 122 586 | Aug 2001 | EP |
| 1 143 270 | Oct 2001 | EP |
| 1 251 454 | Oct 2002 | EP |
| 1251454 | Oct 2002 | EP |
| 1 271 223 | Jan 2003 | EP |
| 1 296 094 | Mar 2003 | EP |
| 1 329 664 | Jul 2003 | EP |
| 1 336 876 | Aug 2003 | EP |
| 1 347 315 | Sep 2003 | EP |
| 1 389 775 | Feb 2004 | EP |
| 1 413 543 | Apr 2004 | EP |
| 1437610 | Jul 2004 | EP |
| 1 519 218 | Mar 2005 | EP |
| 1 577 701 | Sep 2005 | EP |
| 1 748 305 | Jan 2007 | EP |
| 1 762 778 | Mar 2007 | EP |
| 1 975 651 | Oct 2008 | EP |
| 1 988 332 | Nov 2008 | EP |
| 1 988 333 | Nov 2008 | EP |
| 2 315 356 | Jan 1998 | GB |
| 2 331 615 | May 1999 | GB |
| 2 351 834 | Jan 2001 | GB |
| 09 171111 | Jun 1997 | JP |
| 11 160699 | Jun 1999 | JP |
| 11 211999 | Aug 1999 | JP |
| 2000 075293 | Mar 2000 | JP |
| 2000 081848 | Mar 2000 | JP |
| 2000 181367 | Jun 2000 | JP |
| 2000 193933 | Jul 2000 | JP |
| 2001-021883 | Jan 2001 | JP |
| 2002-108227 | Apr 2002 | JP |
| 2002 174732 | Jun 2002 | JP |
| 2002 174780 | Jun 2002 | JP |
| 2002 196152 | Jul 2002 | JP |
| 2002 245835 | Aug 2002 | JP |
| 2003 007114 | Jan 2003 | JP |
| 2003 057653 | Feb 2003 | JP |
| 2003 173713 | Jun 2003 | JP |
| 2003 186008 | Jul 2003 | JP |
| 2003 188959 | Jul 2003 | JP |
| 2003-315694 | Nov 2003 | JP |
| 2003 344881 | Dec 2003 | JP |
| 2004-534280 | Nov 2004 | JP |
| 2005-259365 | Sep 2005 | JP |
| 2006 107993 | Apr 2006 | JP |
| 2008 103110 | May 2008 | JP |
| 567388 | Dec 2003 | TW |
| WO 9406871 | Mar 1994 | WO |
| WO 9501584 | Jan 1995 | WO |
| WO 9819201 | May 1998 | WO |
| WO 9963394 | Dec 1999 | WO |
| WO 9964785 | Dec 1999 | WO |
| WO 0050807 | Aug 2000 | WO |
| WO 0129148 | Apr 2001 | WO |
| WO 0157434 | Aug 2001 | WO |
| WO 0184228 | Nov 2001 | WO |
| WO 0184229 | Nov 2001 | WO |
| WO 02071132 | Sep 2002 | WO |
| WO 03007049 | Jan 2003 | WO |
| WO 03056876 | Jul 2003 | WO |
| WO 2004015489 | Feb 2004 | WO |
| WO 2004088372 | Oct 2004 | WO |
| WO 2004114418 | Dec 2004 | WO |
| WO 2005011012 | Feb 2005 | WO |
| WO 2005111669 | Nov 2005 | WO |
| WO 2007064133 | Jun 2007 | WO |
| WO 2007094558 | Aug 2007 | WO |
| WO 2008038754 | Apr 2008 | WO |
| WO 2008045200 | Apr 2008 | WO |
| WO 2008045207 | Apr 2008 | WO |
| WO 2008045218 | Apr 2008 | WO |
| WO 2008045224 | Apr 2008 | WO |
| WO 2008137299 | Nov 2008 | WO |
| WO 2009011922 | Jan 2009 | WO |
| WO 2009154957 | Dec 2009 | WO |
| Number | Date | Country | |
|---|---|---|---|
| 20090296193 A1 | Dec 2009 | US |
| Number | Date | Country | |
|---|---|---|---|
| 61056601 | May 2008 | US |
