Patent Grant
11327599
Various technologies have been used to detect a touch input on a display area. The most popular technologies today include capacitive and resistive touch detection technology. Using resistive touch technology, often a glass panel is coated with multiple conductive layers that register touches when physical pressure is applied to the layers to force the layers to make physical contact. Using capacitive touch technology, often a glass panel is coated with material that can hold an electrical charge sensitive to a human finger. By detecting the change in the electrical charge due to a touch, a touch location can be detected. However, with resistive and capacitive touch detection technologies, the glass screen is required to be coated with a material that reduces the clarity of the glass screen. Additionally, because the entire glass screen is required to be coated with a material, manufacturing and component costs can become prohibitively expensive as larger screens are desired.
Another type of touch detection technology includes surface acoustic wave technology. One example includes the Elo Touch Systems Acoustic Pulse Recognition, commonly called APR, manufactured by Elo Touch Systems of 301 Constitution Drive, Menlo Park, Calif. 94025. The APR system includes transducers attached to the edges of a touchscreen glass that pick up the sound emitted on the glass due to a touch. However, the surface glass may pick up other external sounds and vibrations that reduce the accuracy and effectiveness of the APR system to efficiently detect a touch input. Another example includes the Surface Acoustic Wave-based technology, commonly called SAW, such as the Elo IntelliTouch Plus™ of Elo Touch Systems. The SAW technology sends ultrasonic waves in a guided pattern using reflectors on the touch screen to detect a touch. However, sending the ultrasonic waves in the guided pattern increases costs and may be difficult to achieve. Detecting additional types of inputs, such as multi-touch inputs, may not be possible or may be difficult using SAW or APR technology.
Additionally, current touch detection technology cannot reliably, accurately, and efficiently detect pressure or force of a touch input. Although prior attempts have been made to detect pressure of touch input by measuring the relative size of a touch input (e.g., as a finger presses harder on a screen, area of the finger contacting the screen proportionally increases), these attempts produce unreliable results when a hard stylus or different sized fingers are used. Therefore there exists a need for a better way to detect an input on a surface. Once force or pressure of a touch input can be reliably detected, user interface interaction utilizing force or pressure may be provided.
Popularity of devices such as tablet computers and smartphones has spawned an ecosystem of software applications utilizing touch input detection. The ability to reliably and efficiently detect touch input location on a display surface has enabled applications to take advantage of new user interface interaction patterns to offer enhanced application usability across a wide range of inexpensive devices. Further enhanced usability may be enabled if it is possible to detect a type of object that is providing the touch input. For example, the ability to distinguish between a human finger and a stylus contacting a touchscreen may be utilized by an application to provide different functionality based on the type of object used to provide the touch input. It has been difficult for prior touch input devices to reliably and inexpensively detect a type of object contacting the touch input surface of a device. Therefore, there exists a need for a way to more efficiently detect a type of object used to provide a touch input.
Various embodiments of the invention are disclosed in the following detailed description and the accompanying drawings.
The invention can be implemented in numerous ways, including as a process; an apparatus; a system; a composition of matter; a computer program product embodied on a computer readable storage medium; and/or a processor, such as a processor configured to execute instructions stored on and/or provided by a memory coupled to the processor. In this specification, these implementations, or any other form that the invention may take, may be referred to as techniques. In general, the order of the steps of disclosed processes may be altered within the scope of the invention. Unless stated otherwise, a component such as a processor or a memory described as being configured to perform a task may be implemented as a general component that is temporarily configured to perform the task at a given time or a specific component that is manufactured to perform the task. As used herein, the term ‘processor’ refers to one or more devices, circuits, and/or processing cores configured to process data, such as computer program instructions.
A detailed description of one or more embodiments of the invention is provided below along with accompanying figures that illustrate the principles of the invention. The invention is described in connection with such embodiments, but the invention is not limited to any embodiment. The scope of the invention is limited only by the claims and the invention encompasses numerous alternatives, modifications and equivalents. Numerous specific details are set forth in the following description in order to provide a thorough understanding of the invention. These details are provided for the purpose of example and the invention may be practiced according to the claims without some or all of these specific details. For the purpose of clarity, technical material that is known in the technical fields related to the invention has not been described in detail so that the invention is not unnecessarily obscured.
Determining a type of object utilized to provide a touch input is disclosed. In some embodiments, a signal that captures a disturbance (e.g., sound, vibration, etc.) by a touch input object contacting a touch input surface is received. For example, when an object contacts a touch input surface, a sound is generated from the object striking the touch input surface and the generated sound is captured by a sensor attached to a medium (e.g., glass) of the touch input surface as an acoustic signal. In some embodiments, the received signal is received from a transducer coupled to a medium of the touch input surface.
At least a portion of the received signal is compared with one or more signatures of one or more touch input object types. For example, for each detectable touch input object type, an associated signature is predetermined (e.g., acoustic signal detected from each sample touch input object type is captured as an signature of the sample touch input object type) and stored in a library of signatures. A type of the touch input object contacting the touch input surface is determined based at least in part on the comparison. For example, if at least a portion of the received signal matches a predetermined signature corresponding to a particular touch input object type, the particular touch input object type is identified as the type of touch input object contacting the touch input surface.
Detecting a force of a touch input is disclosed. In some embodiments, an acoustic transducer transmits an acoustic wave through a medium of a touch input surface. The acoustic wave may be scattered by the touch input producing a scattered acoustic wave. An acoustic detector that detects the scattered acoustic wave and the acoustic detector outputs a signal indicating variation of the acoustic wave that is indicative of an amount of force associated with the touch input. In some embodiments, the force of a touch input is associated with the amount of deflection or movement of a touch surface medium caused by a touch input. For example, as a finger or stylus touches and pushes a touch input surface harder, the amount of force detected gets functionally larger as well. The pressure of a touch input is the force of touch input per unit area of the touch input. For example, the total force of a touch input divided by the area of contact of the touch input equals the pressure of the touch input. Although force of a touch input is utilized in the specification, pressure of a touch input may be used as well. In some cases, when a user pushes harder on a surface such as a touch screen display with a fingertip, the pressure of the touch input may stay substantially constant because the size of the fingertip in contact with the surface becomes larger due to the softness of the fingertip. In order to detect that the user is pushing harder on the surface, the total force of the touch input may be used instead of the pressure of the touch input. In some embodiments, a force of a touch input is used to provide user interface interaction.
In some embodiments, a user touch input on the glass surface of a display screen is detected. In some embodiments, a signal such as an acoustic or ultrasonic signal is propagated freely through a propagating medium with a surface using a transmitter coupled to the medium. When the surface is touched, the propagated signal is disturbed (e.g., the touch causes an interference with the propagated signal). In some embodiments, the disturbed signal is received at a sensor coupled to the propagating medium. By processing the received signal and comparing it against an expected signal without the disturbance, a location on the surface associated with the touch input is at least in part determined. For example, the disturbed signal is received at a plurality of sensors and a relative time difference between when the disturbed signal was received at different sensors is used to determine the location on the surface. In various embodiments, the touch includes a physical contact to a surface using a human finger, pen, pointer, stylus, and/or any other body parts or objects that can be used to contact or disturb the surface. In some embodiments, the touch includes an input gesture and/or a multi-touch input.
In some embodiments, the disturbed signal is used to determine one or more of the following associated with a touch input: a gesture, a coordinate position, a time, a time frame, a direction, a velocity, a force magnitude, a proximity magnitude, a pressure, a size, and other measurable or derived parameters. In some embodiments, by detecting disturbances of a freely propagated signal, touch input detection technology can be applied to larger surface regions with less or no additional cost due to a larger surface region as compared to certain previous touch detection technologies. Additionally, the optical transparency of a touch screen may not have to be affected as compared to resistive and capacitive touch technologies. Merely by way of example, the touch detection described herein can be applied to a variety of objects such as a kiosk, an ATM, a computing device, an entertainment device, a digital signage apparatus, a cell phone, a tablet computer, a point of sale terminal, a food and restaurant apparatus, a gaming device, a casino game and application, a piece of furniture, a vehicle, an industrial application, a financial application, a medical device, an appliance, and any other objects or devices having surfaces.
Propagating signal medium 102 is coupled to sensor 124. For example, sensor 124 is coupled to one surface of propagating signal medium 102 and the same or another surface (e.g., opposing surface) of propagating signal medium 102 may be configured to receive a touch input. The location of sensor 124 on propagating signal medium 102, as shown in
Acoustic processor 126 receives signal detected by sensor 124. The received signal may be processed by acoustic processor 126 to identify a number of touch input contacts received on medium 102 and/or a type of object used to contact medium 102 to provide a touch input. In some embodiments, the received signal may be processed/filtered to reduce noise. For example, a component of the received signal that is likely not associated with an acoustic noise of a touch input is filtered/removed. In order to detect noise, one or more signals from sensors 112, 114, 116, and 118 may be utilized. In some embodiments, acoustic processor 126 utilizes a database/library of touch input object waveform signatures to detect a type of object used to contact medium 102. The database may be stored in acoustic processor 126 and/or an external database may be utilized. Acoustic processor 126 outputs one or more identifiers of a number of received touch input contacts and/or type(s) of object(s) used to provide touch input contact(s) to touch detector 120 and/or application system 122. For example, the identifier number of received touch input contacts may be used by touch detector 120 to determine a touch input location for each of the received touch input contacts and the type of identifier may be used by application system 122 to provide different application functionality based on the type of identifier. In an alternative embodiment, the functionality of acoustic processor 126 is provided by touch detector 120 and acoustic processor 126 is not utilized. In some embodiments, acoustic processor 126 and touch detector 120 are integrated on a same chip.
In some embodiments, acoustic processor 126 may be powered down when idle, waiting for an appropriate contact event to be detected by sensors 112, 114, 116, 118, or 124 and/or touch detector 120. In an example where the touch input surface is the screen of a mobile computing device, the device could be in a low power state until an appropriate event is detected to “wakeup” the device.
Although the example of
Examples of transmitters 104, 106, 108, and 110 include piezoelectric transducers, electromagnetic transducers, transmitters, sensors, and/or any other transmitters and transducers capable of propagating a signal through medium 102. Examples of sensors 112, 114, 116, 118, and 124 include piezoelectric transducers, electromagnetic transducers, laser vibrometer transmitters, and/or any other sensors and transducers capable of detecting a signal on medium 102. In some embodiments, a transducer is designed to convert acoustic and/or vibrational energy on the touch input surface to an electronic signal for processing. In some embodiments, the transmitters and sensors shown in
Touch detector 120 is connected to the transmitters and sensors shown in
In some embodiments, a touch input is received at location 130 on a surface of medium 102. For example, a user touches the surface of medium 102 at location 130. In some embodiments, one or more of transmitters 104, 106, 108, and 110 transmit one or more active signals that are propagated through medium 102. The touch input at location 130 disturbs (e.g., scatters) the propagated signal(s) and the disturbed signals are received at sensors 112, 114, 116, and 118. By measuring the disturbance(s) of the propagated signal(s), the location and/or a force associated with the touch input may be determined.
A signal detected from a sensor such as sensor 112 of
A result of DSP engine 220 may be used by microprocessor 206 to determine a location associated with a user touch input. For example, microprocessor 206 determines a hypothesis location where a touch input may have been received and calculates an expected signal that is expected to be generated if a touch input was received at the hypothesis location and the expected signal is compared with a result of DSP engine 220 to determine whether a touch input was provided at the hypothesis location.
Interface 208 provides an interface for microprocessor 206 and controller 210 that allows an external component to access and/or control detector 202. For example, interface 208 allows detector 202 to communicate with application system 122 of
At 304, signal transmitters and sensors are calibrated. In some embodiments, calibrating the transmitter includes calibrating a characteristic of a signal driver and/or transmitter (e.g., strength). In some embodiments, calibrating the sensor includes calibrating a characteristic of a sensor (e.g., sensitivity). In some embodiments, the calibration of 304 is performed to optimize the coverage and improve signal-to-noise transmission/detection of a signal (e.g., acoustic or ultrasonic) to be propagated through a medium and/or a disturbance to be detected. For example, one or more components of the system of
At 306, surface disturbance detection is calibrated. In some embodiments, a test signal is propagated through a medium such as medium 102 of
In some embodiments, data determined using one or more steps of
At 308, a validation of a touch detection system is performed. For example, the system of
At 402, a signal that can be used to propagate an active signal through a surface region is sent. In some embodiments, sending the signal includes driving (e.g., using driver 214 of
At 404, the active signal that has been disturbed by a disturbance of the surface region is received. The disturbance may be associated with a user touch indication. In some embodiments, the disturbance causes the active signal that is propagating through a medium to be attenuated and/or delayed. In some embodiments, the disturbance in a selected portion of the active signal corresponds to a location on the surface that has been indicated (e.g., touched) by a user.
At 406, the received signal is processed to at least in part determine a location associated with the disturbance. In some embodiments, receiving the received signal and processing the received signal are performed on a periodic interval. For example, the received signal is captured in 5 ms intervals and processed. In some embodiments, determining the location includes extracting a desired signal from the received signal at least in part by removing or reducing undesired components of the received signal such as disturbances caused by extraneous noise and vibrations not useful in detecting a touch input. In some embodiments, determining the location includes processing the received signal and comparing the processed received signal with a calculated expected signal associated with a hypothesis touch contact location to determine whether a touch contact was received at the hypothesis location of the calculated expected signal. Multiple comparisons may be performed with various expected signals associated with different hypothesis locations until the expected signal that best matches the processed received signal is found and the hypothesis location of the matched expected signal is identified as the touch contact location(s) of a touch input. For example, signals received by sensors (e.g., sensors 112, 114, 116, and 118 of
The location, in some embodiments, is one or more locations (e.g., location coordinate(s)) on the surface region where a user has provided a touch contact. In addition to determining the location, one or more of the following information associated with the disturbance may be determined at 406: a gesture, simultaneous user indications (e.g., multi-touch input), a time, a status, a direction, a velocity, a force magnitude, a proximity magnitude, a pressure, a size, and other measurable or derived information. In some embodiments, the location is not determined at 406 if a location cannot be determined using the received signal and/or the disturbance is determined to be not associated with a user input. Information determined at 406 may be provided and/or outputted.
Although
At 502, a received signal is conditioned. In some embodiments, the received signal is a signal including a pseudorandom binary sequence that has been freely propagated through a medium with a surface that can be used to receive a user input. For example, the received signal is the signal that has been received at 404 of
At 504, an analog to digital signal conversion is performed on the signal that has been conditioned at 502. In various embodiments, any number of standard analog to digital signal converters may be used.
At 506, a time domain signal capturing a received signal time delay caused by a touch input disturbance is determined. In some embodiments, determining the time domain signal includes correlating the received signal (e.g., signal resulting from 504) to locate a time offset in the converted signal (e.g., perform pseudorandom binary sequence deconvolution) where a signal portion that likely corresponds to a reference signal (e.g., reference pseudorandom binary sequence that has been transmitted through the medium) is located. For example, a result of the correlation can be plotted as a graph of time within the received and converted signal (e.g., time-lag between the signals) vs. a measure of similarity. In some embodiments, performing the correlation includes performing a plurality of correlations. For example, a coarse correlation is first performed then a second level of fine correlation is performed. In some embodiments, a baseline signal that has not been disturbed by a touch input disturbance is removed in the resulting time domain signal. For example, a baseline signal (e.g., determined at 306 of
At 508, the time domain signal is converted to a spatial domain signal. In some embodiments, converting the time domain signal includes converting the time domain signal determined at 506 into a spatial domain signal that translates the time delay represented in the time domain signal to a distance traveled by the received signal in the propagating medium due to the touch input disturbance. For example, a time domain signal that can be graphed as time within the received and converted signal vs. a measure of similarity is converted to a spatial domain signal that can be graphed as distance traveled in the medium vs. the measure of similarity.
In some embodiments, performing the conversion includes performing dispersion compensation. For example, using a dispersion curve characterizing the propagating medium, time values of the time domain signal are translated to distance values in the spatial domain signal. In some embodiments, a resulting curve of the time domain signal representing a distance likely traveled by the received signal due to a touch input disturbance is narrower than the curve contained in the time domain signal representing the time delay likely caused by the touch input disturbance. In some embodiments, the time domain signal is filtered using a match filter to reduce undesired noise in the signal. For example, using a template signal that represents an ideal shape of a spatial domain signal, the converted spatial domain signal is match filtered (e.g., spatial domain signal correlated with the template signal) to reduce noise not contained in the bandwidth of the template signal. The template signal may be predetermined (e.g., determined at 306 of
At 510, the spatial domain signal is compared with one or more expected signals to determine a touch input captured by the received signal. In some embodiments, comparing the spatial domain signal with the expected signal includes generating expected signals that would result if a touch contact was received at hypothesis locations. For example, a hypothesis set of one or more locations (e.g., single touch or multi-touch locations) where a touch input might have been received on a touch input surface is determined, and an expected spatial domain signal that would result at 508 if touch contacts were received at the hypothesis set of location(s) is determined (e.g., determined for a specific transmitter and sensor pair using data measured at 306 of
The proximity of location(s) of a hypothesis set to the actual touch contact location(s) captured by the received signal may be proportional to the degree of similarity between the expected signal of the hypothesis set and the spatial signal determined at 508. In some embodiments, signals received by sensors (e.g., sensors 112, 114, 116, and 118 of
At 602, a first correlation is performed. In some embodiments, performing the first correlation includes correlating a received signal (e.g., resulting converted signal determined at 504 of
At 604, a second correlation is performed based on a result of the first correlation. Performing the second correlation includes correlating (e.g., cross-correlation or convolution similar to step 602) a received signal (e.g., resulting converted signal determined at 504 of
At 702, a number of simultaneous touch contacts included in a touch input is determined. In some embodiments, when detecting a location of a touch contact, the number of simultaneous contacts being made to a touch input surface (e.g., surface of medium 102 of
At 704, one or more hypothesis sets of one or more touch contact locations associated with the determined number of simultaneous touch contacts are determined. In some embodiments, it is desired to determine the coordinate locations of fingers touching a touch input surface. In some embodiments, in order to determine the touch contact locations, one or more hypothesis sets are determined on potential location(s) of touch contact(s) and each hypothesis set is tested to determine which hypothesis set is most consistent with a detected data.
In some embodiments, determining the hypothesis set of potential touch contact locations includes dividing a touch input surface into a constrained number of points (e.g., divide into a coordinate grid) where a touch contact may be detected. For example, in order to initially constrain the number of hypothesis sets to be tested, the touch input surface is divided into a coordinate grid with relatively large spacing between the possible coordinates. Each hypothesis set includes a number of location identifiers (e.g., location coordinates) that match the number determined in 702. For example, if two was determined to be the number in 702, each hypothesis set includes two location coordinates on the determined coordinate grid that correspond to potential locations of touch contacts of a received touch input. In some embodiments, determining the one or more hypothesis sets includes determining exhaustive hypothesis sets that exhaustively cover all possible touch contact location combinations on the determined coordinate grid for the determined number of simultaneous touch contacts. In some embodiments, a previously determined touch contact location(s) of a previous determined touch input is initialized as the touch contact location(s) of a hypothesis set.
At 706, a selected hypothesis set is selected among the one or more hypothesis sets of touch contact location(s) as best corresponding to touch contact locations captured by detected signal(s). In some embodiments, one or more propagated active signals (e.g., signal transmitted at 402 of
At 708, it is determined whether additional optimization is to be performed. In some embodiments, determining whether additional optimization is to be performed includes determining whether any new hypothesis set(s) of touch contact location(s) should be analyzed in order to attempt to determine a better selected hypothesis set. For example, a first execution of step 706 utilizes hypothesis sets determined using locations on a larger distance increment coordinate grid overlaid on a touch input surface and additional optimization is to be performed using new hypothesis sets that include locations from a coordinate grid with smaller distance increments. Additional optimizations may be performed any number of times. In some embodiments, the number of times additional optimizations are performed is predetermined. In some embodiments, the number of times additional optimizations are performed is dynamically determined. For example, additional optimizations are performed until a comparison threshold indicator value for the selected hypothesis set is reached and/or a comparison indicator for the selected hypothesis does not improve by a threshold amount. In some embodiments, for each optimization iteration, optimization may be performed for only a single touch contact location of the selected hypothesis set and other touch contact locations of the selected hypothesis may be optimized in a subsequent iteration of optimization.
If at 708 it is determined that additional optimization should be performed, at 710, one or more new hypothesis sets of one or more touch contact locations associated with the number of the touch contacts are determined based on the selected hypothesis set. In some embodiments, determining the new hypothesis sets includes determining location points (e.g., more detailed resolution locations on a coordinate grid with smaller distance increments) near one of the touch contact locations of the selected hypothesis set in an attempt to refine the one of the touch contact locations of the selected hypothesis set. The new hypothesis sets may each include one of the newly determined location points, and the other touch contact location(s), if any, of a new hypothesis set may be the same locations as the previously selected hypothesis set. In some embodiments, the new hypothesis sets may attempt to refine all touch contact locations of the selected hypothesis set. The process proceeds back to 706, whether or not a newly selected hypothesis set (e.g., if previously selected hypothesis set still best corresponds to detected signal(s), the previously selected hypothesis set is retained as the new selected hypothesis set) is selected among the newly determined hypothesis sets of touch contact location(s).
If at 708 it is determined that additional optimization should not be performed, at 714, the selected hypothesis set is indicated as the detected location(s) of touch contact(s) of the touch input. For example, a location coordinate(s) of a touch contact(s) is provided.
At 802, for each hypothesis set (e.g., determined at 704 of
In some embodiments, in the event the hypothesis set includes more than one touch contact location (e.g., multi-touch input), expected signal for each individual touch contact location is determined separately and combined together. For example, an expected signal that would result if a touch contact was provided at a single touch contact location is added with other single touch contact expected signals (e.g., effects from multiple simultaneous touch contacts add linearly) to generate a single expected signal that would result if the touch contacts of the added signals were provided simultaneously.
In some embodiments, the expected signal for a single touch contact is modeled as the function:
C*P(x−d)
where C is a function coefficient (e.g., complex coefficient) and P(x) is a function and d is the total path distance between a transmitter (e.g., transmitter of a signal desired to be simulated) to a touch input location and between the touch input location and a sensor (e.g., receiver of the signal desired to be simulated).
In some embodiments, the expected signal for one or more touch contacts is modeled as the function:
where j indicates which touch contact and N is the number of total simultaneous touch contacts being modeled (e.g., number of contacts determined at 702 of
At 804, corresponding detected signals are compared with corresponding expected signals. In some embodiments, the detected signals include spatial domain signals determined at 508 of
where ε(rx, tx) is the cost function, q(x) is the detected signal, and Σj=1NCjP(x−dj) is the expected signal. In some embodiments, the global cost function for a hypothesis set analyzed for more than one (e.g., all) transmitter/sensor pair is modeled as:
where ε is the global cost function, Z is the number of total transmitter/sensor pairs, i indicates the particular transmitter/sensor pair, and ε(rx,tx)i is the cost function of the particular transmitter/sensor pair.
At 806, a selected hypothesis set of touch contact location(s) is selected among the one or more hypothesis sets of touch contact location(s) as best corresponding to detected signal(s). In some embodiments, the selected hypothesis set is selected among hypothesis sets determined at 704 or 710 of
At 902, a detected signal is received. The detected signal may be an acoustic signal. In some embodiments, the acoustic signal captures a sound/vibration generated due to one or more objects contacting a touch input surface such as the surface of medium 102 of
At 904, the received signal is filtered to reduce noise included in the received acoustic signal. In some embodiments, background audio, such as human speech or music, could potentially create false contact events without proper filtering and/or pulse qualification. In some embodiments, a rate of spectral change of a portion of the received signal is measured. For example, by exploiting the observation that background noise can be viewed as statistically stationary over the span of tens of milliseconds, signal portions with a relative lower rate of spectral change are identified as background noise not capturing a touch contact event. In some embodiments, a fast Fourier transform of the received acoustic signal is determined over a short time extent (e.g., less than 10 milliseconds). If a signal portion with a slow change is detected (e.g., below a threshold value), the signal portion is reduced and/or removed to filter the received signal. In some embodiments, filtering the received signal is optional. In some embodiments, filtering the received signal includes removing/reducing one or more components of an active signal included in the received signal. For example, a baseline signal (e.g., determined at 306 of
At 906, a number of simultaneous (e.g., within a threshold amount of time) touch contacts captured in the received signal is determined. In some embodiments, the number of touch contacts (e.g., fingers) touching a touch input surface may be determined by “counting” the number of touches/contacts (e.g., determine the number of times detected acoustic signal is above a threshold level) within a predetermined amount of time. For example, when a user intends to touch a touch input screen with multiple fingers at the same time, it is rare for the fingers to land on the screen at the same time. There will likely be a small delay between when the fingers land on the touch surface. The number of impacts (e.g., determined by analyzing acoustic signal received from sensor 124 of
At 908, the determined number of touch contacts is provided. In some embodiments, the number determined at 906 is provided to a process (e.g., provided at step 702 of
At 1002, a detected signal is received. The detected signal may be an acoustic signal. In some embodiments, the acoustic signal captures a sound/vibration generated due to one or more objects contacting a touch input surface such as the surface of medium 102 of
At 1004, the received signal is filtered to reduce noise included in the received signal. In some embodiments, background audio, such as human speech or music, could potentially create false contact events without proper filtering. In some embodiments, a rate of spectral change of a portion of the received signal is measured. For example, by exploiting the observation that background noise can be viewed as statistically stationary over the span of tens of milliseconds, signal portions with a relative lower rate of spectral change are identified as background noise not capturing a touch contact event. In some embodiments, a fast Fourier transform of the received acoustic signal is determined over a short time extent (e.g., less than 10 milliseconds). If a signal component with a slow change is detected (e.g., below a threshold value), the signal portion is reduced and/or removed to filter the received signal. In some embodiments, filtering the received signal is optional. In some embodiments, filtering the received signal includes removing/reducing one or more components of an active signal included in the received signal. For example, a baseline signal (e.g., determined at 306 of
At 1006, a type of object used to provide a touch contact is determined. In some embodiments, determining the type of object includes determining whether the touch contact of a touch input was provided using a finger (e.g., which finger), a stylus (e.g., which stylus or tip of stylus), or other detectable object. In some embodiments, determining the type of object includes analyzing an energy/signal captured in the received/filtered signal due to the touch contact of the object on a touch input surface. In some embodiments, portion(s) of the received/filtered signal that are each associated with a touch contact are identified. For example, using at least a portion of the process of
In some embodiments, at least a portion of the received/filtered signal corresponding to a touch input contact is analyzed to determine whether it matches a known signature (e.g., acoustic signature waveform) of a known object type. For example, a finger touching a touch input surface may be characterized by a different detected acoustic signature as compared to a harder object such as a pen or a stylus. A different waveform signature associated with each detectable object type may be compared to at least a portion of the received/filtered signal to determine the type of the object contacting the touch input surface. In some embodiments, the object type waveform signatures are predetermined and stored in a dictionary/data structure. For example, for each object type desired to be detectable, a sample signal of the object contacting a sample touch input surface is captured and characterized as the object type waveform signature of the object. If at least a portion of the received/filtered signature matches (e.g., within a threshold difference) one of the predetermined signatures, an object type associated with the matched signature is identified as the object type of the portion of the received/filtered signal.
In some embodiments, determining the object type of the touch contact includes feature matching in the time domain by correlating a waveform of at least a portion of the received/filtered signal against a known “dictionary” of waveforms from contact events. In some embodiments, determining the object type of the touch contact includes frequency-domain matching of at least a portion of the received/filtered signal against a known “dictionary” of frequency-domain spectra from contact events. In some embodiments, determining the object type of the touch contact includes wavelet-domain matching of at least a portion of the received/filtered signal against a known “dictionary” of wavelet-domain transforms from contact events.
At 1008, the identified touch contact object type is provided. In some embodiments, the type determined at 1006 is provided to an application (e.g., to application system 122) to provide an interaction/functionality based on the identified object type. In some embodiments, differentiation between a stylus or pen contact versus a human finger can be used to initiate different behaviors on a device. For example, detection of a stylus contact may invoke handwriting detection on an application.
At 1204, an analog to digital signal conversion is performed on the signal that has been conditioned at 1202. In various embodiments, any number of standard analog to digital signal converters may be used. The resulting digital signal is used to perform a first correlation at 1206. In some embodiments, performing the first correlation includes correlating the converted signal with a reference signal. Performing the correlation includes cross-correlating or determining a convolution (e.g., interferometry) of the converted signal with a reference signal to measure the similarity of the two signals as a time-lag is applied to one of the signals. By performing the correlation, the location of a portion of the converted signal that most corresponds to the reference signal can be located. For example, a result of the correlation can be plotted as a graph of time within the received and converted signal (e.g., time-lag between the signals) vs. a measure of similarity. The associated time value of the largest value of the measure of similarity corresponds to the location where the two signals most correspond. By comparing this measured time value against a reference time value (e.g., at 306 of
At 1208, a second correlation is performed based on a result of the first correlation. Performing the second correlation includes correlating (e.g., cross-correlation or convolution similar to step 1206) the converted signal in 1204 with a second reference signal. The second reference signal is a more complex/detailed (e.g., more computationally intensive) reference signal as compared to the first reference signal used in 1206. In some embodiments, the second correlation is performed in 1208 because using the second reference signal in 1206 may be too computationally intensive for the time interval required to be correlated in 1206. Performing the second correlation based on the result of the first correlation includes using one or more time values determined as a result of the first correlation. For example, using a result of the first correlation, a range of likely time values (e.g., time-lag) that most correlate between the received signal and the first reference signal is determined and the second correlation is performed using the second reference signal only across the determined range of time values to fine tune and determine the time value that most corresponds to where the second reference signal (and, by association, also the first reference signal) matched the received signal. In various embodiments, the first and second correlations have been used to determine a portion within the received signal that correspond to a disturbance caused by a touch input at a location on a surface of a propagating medium. In other embodiments, the second correlation is optional. For example, only a single correlation step is performed.
At 1210, a result of the second correlation is used to at least in part determine a location associated with a disturbance. In some embodiments, determining the location includes comparing a determined time value where the signals of the second correlation are most correlated and comparing the determined time value with a reference time value (e.g., determined at 306 of
At 1304, time differences associated with the plurality of results are used to determine a location associated with the disturbance. In some embodiments, each of the time differences is associated with a time when signals used in the correlation are most correlated. In some embodiments, the time differences are associated with a determined time delay/offset or phase difference caused on the received signal due to the disturbance. This time delay may be calculated by comparing a time value determined using a correlation with a reference time value that is associated with a scenario where a touch input has not been specified. The result of the comparison may be used to calculate a location of the disturbance relative to the locations of sensors that received the plurality of signals. By using the location of the sensors relative to a surface of a medium that has propagated the received signal, a location on the surface where the disturbance originated may be determined.
At 1402, a location associated with a user input on a touch input surface is determined. In some embodiments, at least a portion of the process of
At 1404, one or more received signals are selected to be evaluated. In some embodiments, selecting the signal(s) to be evaluated include selecting one or more desired signals from a plurality of received signals used to detect the location associated with the user input. For example, one or more signals received in step 404 of
In some embodiments, a variation (e.g., disturbance such as amplitude change) detected in an active signal received at a receiver/sensor may be greater at certain receivers (e.g., receivers located closest to the location of the touch input) as compared to other receivers. For example, in the example of
At 1406, the one or more selected signals are normalized. In some embodiments, normalizing a selected signal includes adjusting (e.g., scaling) an amplitude of the selected signal based on a distance value associated with the selected signal. For example, although an amount/intensity of force of a touch input may be detected by measuring an amplitude of a received active signal that has been disturbed by the force of the touch input, other factors such as the location of the touch input with respect to a receiver that has received the disturbed signal and/or location of the transmitter transmitting the active signal may also affect the amplitude of the received signal used to determine the intensity of the force. In some embodiments, a distance value/identifier associated with one or more of the following is used to determine a scaling factor used to scale a selected signal: a distance between a location of a touch input and a location of a receiver that has received the selected signal, a distance between a location of a touch input and a location of a transmitter that has transmitted an active signal that has been disturbed by a touch input and received as the selected signal, a distance between a location of a receiver that has received the selected signal and a location of a transmitter that has transmitted an active signal that has been disturbed by a touch input and received as the selected signal, and a combined distance of a first distance between a location of a touch input and a location of a receiver that has received the selected signal and a second distance between the location of the touch input and a location of a transmitter that has transmitted an active signal that has been disturbed by a touch input and received as the selected signal. In some embodiments, each of one or more selected signals is normalized by a different amount (e.g., different amplitude scaling factors).
At 1408, a force intensity identifier associated with the one or more normalized signals is determined. The force intensity identifier may include a numerical value and/or other identifier identifying a force intensity. In some embodiments, if a plurality of normalized signals is used, an associated force may be determined for each normalized signal and the determined forces may be averaged and/or weighted-averaged to determine the amount of the force. For example, in the case of weighted averaging of the force values, each determined force value is weighted based on an associated signal-to-noise ratio, an associated amplitude value, and/or an associated distance value between a receiver of the normalized signal and the location of the touch input.
In some embodiments, the amount of force is determined using a measured amplitude associated with a disturbed portion of the normalized signal. For example, the normalized signal represents a received active signal that has been disturbed when a touch input was provided on a surface of a medium that was propagating the active signal. A reference signal may indicate a reference amplitude of a received active signal if the active signal was not disturbed by a touch input. In some embodiments, an amplitude value associated with an amplitude change to the normalized signal caused by a force intensity of a touch input is determined. For example, the amplitude value may be a measured amplitude of a disturbance detected in a normalized signal or a difference between a reference amplitude and the measured amplitude of the disturbance detected in the normalized signal. In some embodiments, the amplitude value is used to obtain an amount/intensity of a force.
In some embodiments, the use of the amplitude value includes using the amplitude value to look up in a data structure (e.g., table, database, chart, graph, lookup table, list, etc.) a corresponding associated force intensity. For example, the data structure includes entries associating a signal disturbance amplitude value and a corresponding force intensity identifier. The data structure may be predetermined/pre-computed. For example, for a given device, a controlled amount of force is applied and the disturbance effect on an active signal due to the controlled amount of force is measured to determine an entry for the data structure. The force intensity may be varied to determine other entries of the data structure. In some embodiments, the data structure is associated with a specific receiver that received the signal included in the normalized signal. For example, the data structure includes data that has been specifically determined for characteristics of a specific receiver (e.g., for sensor/receiver 114 of
In some embodiments, the use of the amplitude value includes using the amplitude value in a formula that can be used to simulate and/or calculate a corresponding force intensity. For example, the amplitude value is used as an input to a predetermined formula used to compute a corresponding force intensity. In some embodiments, the formula is associated with a specific receiver that received the signal of the normalized signal. For example, the formula includes one or more parameters (e.g., coefficients) that have been specifically determined for characteristics of a specific receiver (e.g., for sensor/receiver 114 of
At 1410, the determined force intensity identifier is provided. In some embodiments, providing the force intensity identifier includes providing the identifier (e.g., a numerical value, an identifier within a scale, etc.) to an application such as an application of application system 122 of
At 1502, a controlled amount of force is applied at a selected location on a touch input surface. In some embodiments, the force is provided on a location of a surface of medium 102 of
At 1504, an effect of the applied force is measured using one or more receivers. Examples of the receivers include sensors 112-118 of
A reference signal may indicate a reference amplitude of a received active signal that has not been disturbed by a touch input. In some embodiments, an amplitude value associated with an amplitude change caused by a disturbance of a touch input is determined. For example, the amplitude value may be a measured amplitude value of a disturbance detected in a normalized signal or a difference between a reference amplitude and the measured amplitude value of the disturbance detected in the normalized signal. In some embodiments, the amplitude value is used to obtain an identifier of a force intensity.
In some embodiments, a distance value associated with one or more of the following is used to determine a scaling factor used to scale a received signal before an effect of a disturbance is measured using the received signal: a distance between a location of a touch input and a location of a receiver that has received the selected signal, a distance between a location of the force input and a location of a transmitter that has transmitted an active signal that has been disturbed by the force input and received by the receiver, a distance between a location of the receiver and a location of a transmitter that has transmitted an active signal that has been disturbed by the force input and received by the receiver, and a combined distance of a first distance between a location of a force input and a location of the receiver and a second distance between the location of the force input and a location of a transmitter that has transmitted an active signal that has been disturbed by the force input and received by the receiver. In some embodiments, each of one or more signals received by different receivers is normalized by a different amount (e.g., different amplitude scaling factors).
At 1506, data associated with the measured effect is stored. In some embodiments, storing the data includes storing an entry in a data structure such as the data structure that may be used in step 1408 of
In some embodiments, the process of
At 1702, forces associated with each touch input location point of a plurality of touch input location points are determined. In some embodiments, a user touch input may be represented by a plurality of touch input locations (e.g., multi-touch input, touch input covering a relatively large area, etc.). In some embodiments, for each touch input location point, at least a portion of the process of
At 1704, the determined forces are combined to determine a combined force. For example, the combined force represents a total amount of force applied on a touch input surface. In some embodiments, combining the forces includes adding a numerical representation of the forces together to determine the combined force. In some embodiments, a numerical representation of each determined force is weighted before being added together. For example, each numerical value of a determined force is weighted (e.g., multiplied by a scalar) based on an associated signal-to-noise ratio, an associated amplitude value, and/or an associated distance value between a receiver and a location of a touch input. In some embodiments, the weights of the forces being weighted must sum to the number of forces being combined.
At 1706, the combined force is provided. In some embodiments, providing the combined force includes providing a force intensity identifier to an application such as an application of application system 122 of
At 1802, one or more indicators associated with a location and a force intensity of a user input are received. In some embodiments, the indicator(s) include data provided in step 1410 of
At 1804, a user interface object associated with the location is determined. In some embodiments, the user input is a touch screen user interface input and the user interface element desired to be indicated by the user input is determined. For example, the user input is detected at a location where an icon has been displayed and it is determined that a user has desired to select the user icon by providing a touch input at a location of the icon. In some embodiments, the user interface object includes an object displayed on a touchscreen. In some embodiments, the user interface object is not an object already displayed on a screen. For example, a hidden keyboard user interface object appears when a user touches a specific area of a touch input screen.
At 1806, a user interface interaction based at least in part on the user interface object and the force intensity is provided. For example, a user may indicate a desired user interface action by varying the amount of force applied on a touch input surface and the user interaction indicated by the received data in 1102 is provided. Examples of the possible user interface interactions are described in the following paragraphs.
In some embodiments, a touch input gesture and a force associated with the gesture indicates that a virtual keyboard should be displayed and/or not displayed. For example, when a predetermined number of distinct touch inputs are detected simultaneously (e.g., 4 or 5 fingers of each hand resting on a touch input surface), a keyboard is displayed. In some embodiments, a displayed virtual keyboard is oriented and/or located on a screen based at least in part on one or more touch inputs received. For example, a virtual keyboard is oriented and placed on a touch input display surface such that when fingers of a user are rested on the surface, the keys of the home row of the virtual keyboard are placed under the location and orientation of the placed fingers of the user to place the virtual keyboard in standard touch typing position with respect to the user's fingers. The keyboard may be split to match the orientation of fingers of the user's two hands. Diagram 2300 shows a virtual keyboard that has been displayed for a user that has placed fingers of the user's left hand higher and angled out as compared to fingers of the user's right hand that has been placed lower in the opposite angle. In some embodiments, a touch input to a key of the virtual keyboard of diagram 2300 is only registered as a keyboard key press if the force of the touch input is above a threshold. The threshold levels may be preconfigured, dynamically determined, and/or configurable.
In some embodiments, force information of touch input is used to distinguish between different gestures that otherwise might be identical or very similar. For example, a swipe touchscreen gesture of a first force intensity within a first threshold range may be interpreted as a scrolling/panning indication and a swipe touchscreen gesture of a second force intensity within a second threshold range may be interpreted as a “change to the next window/tab” indication.
In some embodiments, a speed or precision of slider bar movement using touch input dragging may be proportional to the force intensity level of the touch input. For example, a slider control moves with detailed/fine precision when “light” pressure is applied but moves with coarse/faster precision when “harder” pressure is applied. In some embodiments, the slider bar may be moved with greater (e.g., fine or less granular) precision when a touch input force intensity within a first intensity range is applied and moved with less (e.g., coarse or more granular) precision when a touch input force intensity within a second intensity range is applied. The threshold levels may be preconfigured, dynamically determined, and/or configurable.
In some embodiments, a velocity at which an object such as a finger or stylus contacts a touch input surface is used to control a user interface. For example, video games, virtual musical instruments (drums and pianos are two common examples), and other applications may utilize velocity information to provide desired functionality. In some embodiments, measurement of contact velocity may be achieved by measuring the rate of change of the force. For example, if the touch force changes at a given point from 0 to 0.5 pounds in 20 milliseconds, it can be inferred that the finger or other object impacted the touch input screen at high velocity. On the other hand, a change in force from 0 to 0.1 pounds in 100 milliseconds could be construed as a relatively low velocity. Both the absolute measure of pressure and the rate-of-change of pressure may be useful measures of information in user interface design.
Although the foregoing embodiments have been described in some detail for purposes of clarity of understanding, the invention is not limited to the details provided. There are many alternative ways of implementing the invention. The disclosed embodiments are illustrative and not restrictive.
This application is a continuation in part of pending U.S. patent application Ser. No. 16/578,953 entitled IDENTIFYING A CONTACT TYPE filed Sep. 23, 2019, which is incorporated herein by reference for all purposes, which is a continuation of U.S. patent application Ser. No. 16/243,803 entitled USING A TYPE OF OBJECT TO PROVIDE A TOUCH CONTACT INPUT filed Jan. 9, 2019, now U.S. Pat. No. 10,466,836, which is incorporated herein by reference for all purposes, which is a continuation of U.S. patent application Ser. No. 15/939,911 entitled DETECTION OF TYPE OF OBJECT USED TO PROVIDE A TOUCH CONTACT INPUT filed Mar. 29, 2018, now U.S. Pat. No. 10,209,825, which is incorporated herein by reference for all purposes, which is a continuation of U.S. patent application Ser. No. 14/882,193 entitled DETECTION OF TYPE OF OBJECT USED TO PROVIDE A TOUCH CONTACT INPUT filed Oct. 13, 2015, now U.S. Pat. No. 9,983,718, which is incorporated herein by reference for all purposes, which is a continuation of U.S. patent application Ser. No. 13/945,649 entitled DETECTION OF TYPE OF OBJECT USED TO PROVIDE A TOUCH CONTACT INPUT filed Jul. 18, 2013, now U.S. Pat. No. 9,189,109, which is incorporated herein by reference for all purposes, which claims priority to U.S. Provisional Application No. 61/673,103, entitled DETECTION OF NUMBER OF CONTACT POINTS IN A TOUCH SENSING SYSTEM filed Jul. 18, 2012, which is incorporated herein by reference for all purposes. This application is a continuation in part of pending U.S. patent application Ser. No. 16/227,852 entitled DETECTING TOUCH INPUT FORCE filed Dec. 20, 2018, which is incorporated herein by reference for all purposes, which is a continuation of U.S. patent application Ser. No. 13/681,294 entitled DETECTING TOUCH INPUT FORCE filed Nov. 19, 2012, now U.S. Pat. No. 10,198,097, which is incorporated herein by reference for all purposes, which claims priority to U.S. Provisional Patent Application No. 61/561,697 entitled TOUCH SCREEN SYSTEM UTILIZING ADDITIONAL AXIS INFORMATION filed Nov. 18, 2011, which is incorporated herein by reference for all purposes, and claims priority to U.S. Provisional Patent Application No. 61/561,660 entitled TOUCH SCREEN SYSTEM UTILIZING ADDITIONAL AXIS INFORMATION FOR SELECTED APPLICATIONS filed Nov. 18, 2011, which is incorporated herein by reference for all purposes, and claims priority to U.S. Provisional Patent Application No. 61/673,102 entitled UTILIZING TOUCH PRESSURE INFORMATION IN GRAPHICAL USER INTERFACES filed Jul. 18, 2012, which is incorporated herein by reference for all purposes. U.S. patent application Ser. No. 13/681,294 entitled DETECTING TOUCH INPUT FORCE filed Nov. 19, 2012, now U.S. Pat. No. 10,198,097, is a continuation in part of U.S. patent application Ser. No. 13/451,288 entitled METHOD AND APPARATUS FOR ACTIVE ULTRASONIC TOUCH DEVICES filed Apr. 19, 2012, now U.S. Pat. No. 9,477,350, which is incorporated herein by reference for all purposes, which claims priority to U.S. Provisional Patent Application No. 61/479,331 entitled METHOD AND APPARATUS FOR ACTIVE ULTRASONIC TOUCH DEVICES filed Apr. 26, 2011 which is incorporated herein by reference for all purposes, and claims priority to U.S. Provisional Patent Application No. 61/594,255 entitled TOUCH SCREEN DEVICE SIGNAL DESIGNS AND METHODS filed Feb. 2, 2012 which is incorporated herein by reference for all purposes.
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| 20100141408 | Doy | Jun 2010 | A1 |
| 20100156818 | Burrough | Jun 2010 | A1 |
| 20100165215 | Shim | Jul 2010 | A1 |
| 20100185989 | Shiplacoff | Jul 2010 | A1 |
| 20100188356 | Vu | Jul 2010 | A1 |
| 20100245265 | Sato | Sep 2010 | A1 |
| 20100269040 | Lee | Oct 2010 | A1 |
| 20100277431 | Klinghult | Nov 2010 | A1 |
| 20100283759 | Iso | Nov 2010 | A1 |
| 20100309139 | Ng | Dec 2010 | A1 |
| 20100311337 | Riviere | Dec 2010 | A1 |
| 20100315373 | Steinhauser | Dec 2010 | A1 |
| 20100321312 | Han | Dec 2010 | A1 |
| 20100321325 | Springer | Dec 2010 | A1 |
| 20100321337 | Liao | Dec 2010 | A1 |
| 20110001707 | Faubert | Jan 2011 | A1 |
| 20110001708 | Sleeman | Jan 2011 | A1 |
| 20110012717 | Pance | Jan 2011 | A1 |
| 20110013785 | Kim | Jan 2011 | A1 |
| 20110018695 | Bells | Jan 2011 | A1 |
| 20110025649 | Sheikhzadeh Nadjar | Feb 2011 | A1 |
| 20110042152 | Wu | Feb 2011 | A1 |
| 20110057903 | Yamano | Mar 2011 | A1 |
| 20110063228 | St Pierre | Mar 2011 | A1 |
| 20110080350 | Almalki | Apr 2011 | A1 |
| 20110084912 | Almalki | Apr 2011 | A1 |
| 20110084937 | Chang | Apr 2011 | A1 |
| 20110141052 | Bernstein | Jun 2011 | A1 |
| 20110155479 | Oda | Jun 2011 | A1 |
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| 20110167391 | Momeyer | Jul 2011 | A1 |
| 20110175813 | Sarwar | Jul 2011 | A1 |
| 20110182443 | Gant | Jul 2011 | A1 |
| 20110191680 | Chae | Aug 2011 | A1 |
| 20110199342 | Vartanian | Aug 2011 | A1 |
| 20110213223 | Kruglick | Sep 2011 | A1 |
| 20110222372 | O'Donovan | Sep 2011 | A1 |
| 20110225549 | Kim | Sep 2011 | A1 |
| 20110234545 | Tanaka | Sep 2011 | A1 |
| 20110248978 | Koyama | Oct 2011 | A1 |
| 20110260988 | Colgate | Oct 2011 | A1 |
| 20110260990 | Ali | Oct 2011 | A1 |
| 20110279382 | Pertuit | Nov 2011 | A1 |
| 20110298670 | Jung | Dec 2011 | A1 |
| 20110300845 | Lee | Dec 2011 | A1 |
| 20110304577 | Brown | Dec 2011 | A1 |
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| 20110316790 | Ollila | Dec 2011 | A1 |
| 20120001875 | Li | Jan 2012 | A1 |
| 20120002820 | Leichter | Jan 2012 | A1 |
| 20120007837 | Kent | Jan 2012 | A1 |
| 20120026114 | Lee | Feb 2012 | A1 |
| 20120030628 | Lee | Feb 2012 | A1 |
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| 20120050230 | Harris | Mar 2012 | A1 |
| 20120062564 | Miyashita | Mar 2012 | A1 |
| 20120068939 | Pemberton-Pigott | Mar 2012 | A1 |
| 20120068970 | Pemberton-Pigott | Mar 2012 | A1 |
| 20120081337 | Camp, Jr. | Apr 2012 | A1 |
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| 20120104901 | Jiang | May 2012 | A1 |
| 20120120031 | Thuillier | May 2012 | A1 |
| 20120126962 | Ujii | May 2012 | A1 |
| 20120127088 | Pance | May 2012 | A1 |
| 20120140954 | Ranta | Jun 2012 | A1 |
| 20120144293 | Kim | Jun 2012 | A1 |
| 20120149437 | Zurek | Jun 2012 | A1 |
| 20120188194 | Sulem | Jul 2012 | A1 |
| 20120188889 | Sambhwani | Jul 2012 | A1 |
| 20120194466 | Posamentier | Aug 2012 | A1 |
| 20120194483 | Deluca | Aug 2012 | A1 |
| 20120200517 | Nikolovski | Aug 2012 | A1 |
| 20120206154 | Pant | Aug 2012 | A1 |
| 20120229407 | Harris | Sep 2012 | A1 |
| 20120232834 | Roche | Sep 2012 | A1 |
| 20120235866 | Kim | Sep 2012 | A1 |
| 20120242603 | Engelhardt | Sep 2012 | A1 |
| 20120270605 | Garrone | Oct 2012 | A1 |
| 20120272089 | Hatfield | Oct 2012 | A1 |
| 20120278490 | Sennett | Nov 2012 | A1 |
| 20120280944 | St Pierre | Nov 2012 | A1 |
| 20120282944 | Zhao | Nov 2012 | A1 |
| 20120300956 | Horii | Nov 2012 | A1 |
| 20120306823 | Pance | Dec 2012 | A1 |
| 20130011144 | Amiri Farahani | Jan 2013 | A1 |
| 20130050133 | Brakensiek | Feb 2013 | A1 |
| 20130050154 | Guy | Feb 2013 | A1 |
| 20130057491 | Chu | Mar 2013 | A1 |
| 20130059532 | Mahanfar | Mar 2013 | A1 |
| 20130082970 | Frey | Apr 2013 | A1 |
| 20130127755 | Lynn | May 2013 | A1 |
| 20130141364 | Lynn | Jun 2013 | A1 |
| 20130141365 | Lynn | Jun 2013 | A1 |
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| 20130194208 | Miyanaka | Aug 2013 | A1 |
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| 20130234995 | Son | Sep 2013 | A1 |
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| 20140022189 | Sheng | Jan 2014 | A1 |
| 20140028576 | Shahparnia | Jan 2014 | A1 |
| 20140078070 | Armstrong-Muntner | Mar 2014 | A1 |
| 20140078086 | Bledsoe | Mar 2014 | A1 |
| 20140078109 | Armstrong-Muntner | Mar 2014 | A1 |
| 20140078112 | Sheng | Mar 2014 | A1 |
| 20140185834 | Frömel | Jul 2014 | A1 |
| 20140247230 | Sheng | Sep 2014 | A1 |
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| 20150002415 | Lee | Jan 2015 | A1 |
| 20150002452 | Klinghult | Jan 2015 | A1 |
| 20150009185 | Shi | Jan 2015 | A1 |
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| 20160012348 | Johnson | Jan 2016 | A1 |
| 20160048266 | Smith | Feb 2016 | A1 |
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| 20160070404 | Kerr | Mar 2016 | A1 |
| 20160091308 | Oliaei | Mar 2016 | A1 |
| 20160139717 | Filiz | May 2016 | A1 |
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| 20160179249 | Ballan | Jun 2016 | A1 |
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| 20160282312 | Cable | Sep 2016 | A1 |
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| 1653411 | Aug 2005 | CN |
| 1914585 | Feb 2007 | CN |
| 101133385 | Feb 2008 | CN |
| 101373415 | Feb 2009 | CN |
| 101568898 | Oct 2009 | CN |
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| 103890701 | Jun 2014 | CN |
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| 102016770 | Sep 2016 | CN |
| 103677339 | Jul 2017 | CN |
| 1405256 | Apr 2004 | EP |
| 2315101 | Apr 2011 | EP |
| 2315101 | Jan 2014 | EP |
| 3174208 | May 2017 | EP |
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| 5723499 | May 2015 | JP |
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| Number | Date | Country | |
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| 20210149519 A1 | May 2021 | US |
| Number | Date | Country | |
|---|---|---|---|
| 61673102 | Jul 2012 | US | |
| 61673103 | Jul 2012 | US | |
| 61594255 | Feb 2012 | US | |
| 61561660 | Nov 2011 | US | |
| 61561697 | Nov 2011 | US | |
| 61479331 | Apr 2011 | US |
| Number | Date | Country | |
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| Parent | 15939911 | Mar 2018 | US |
| Child | 16227852 | US | |
| Parent | 14882193 | Oct 2015 | US |
| Child | 15939911 | US | |
| Parent | 13945649 | Jul 2013 | US |
| Child | 14882193 | US | |
| Parent | 13681294 | Nov 2012 | US |
| Child | 13945649 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 16578953 | Sep 2019 | US |
| Child | 17088283 | US | |
| Parent | 16227852 | Dec 2018 | US |
| Child | 17088283 | US | |
| Parent | 13451288 | Apr 2012 | US |
| Child | 13681294 | US |
