Abstract: A method may involve controlling an apparatus to transmit a first ultrasonic wave by sending first electrical signals to a plurality of separate electrode elements proximate an ultrasonic transceiver layer. The method may involve receiving first electrode layer signals, corresponding to reflections of the first ultrasonic wave, from the electrode layer. The method may involve determining, based on the first electrode layer signals, a location of a target object in contact with the apparatus. The location of the target object may correspond with a proximate electrode element. The method may involve controlling the ultrasonic transceiver layer to transmit a second ultrasonic wave by sending second electrical signals to the proximate electrode element and for receiving receiver pixel signals from at least a portion of the plurality of ultrasonic receiver pixels in an area corresponding with the proximate electrode element.

Abstract: Methods, systems, and devices for detection of a protective cover film on a capacitive touch screen are described. A device may include a capacitive touch screen having a surface and a sensor grid underneath the surface having a set of conductive columns and a set of conductive rows. The device may measure a mutual capacitance between a subset of conductive columns or a subset of conductive rows associated with a sensor grid, and compare the measured mutual capacitance between the subset of conductive columns or the subset of conductive rows to a baseline mutual capacitance associated with the set of conductive columns and the set of conductive rows. According to the comparison, the device may determine a presence of a protective layer in contact with the surface of the capacitive touch screen, and adjust an operating characteristic of the sensor grid.

Abstract: An apparatus may include a cover layer, a layer of first metamaterial proximate (or in) the cover layer, a light source system configured for providing light to the layer of first metamaterial and a receiver system. The first metamaterial may include nanoparticles configured to create ultrasonic waves when illuminated by light. The receiver system may include an ultrasonic receiver system configured to receive ultrasonic waves reflected from a target object in contact with, or proximate, a surface of the cover layer. The control system may be configured to receive ultrasonic receiver signals from the ultrasonic receiver system corresponding to the ultrasonic waves reflected from the target object and to perform an authentication process and/or an imaging process that is based, at least in part, on the ultrasonic receiver signals.

Abstract: A fingerprint sensor device includes a sensor substrate, a plurality of sensor circuits over a first surface of the sensor substrate, and a transceiver layer located over the plurality of sensor circuits and the first surface of the sensor substrate. The transceiver layer includes a piezoelectric layer and a transceiver electrode positioned over the piezoelectric layer. The piezoelectric layer and the transceiver electrode are configured to generate one or more ultrasonic waves or to receive one or more ultrasonic waves. The fingerprint sensor device may include a cap coupled to the sensor substrate and a cavity formed between the cap and the sensor substrate. The cavity and the sensor substrate may form an acoustic barrier.

Abstract: A method may involve controlling an apparatus to transmit a first ultrasonic wave by sending first electrical signals to a plurality of separate electrode elements proximate an ultrasonic transceiver layer. The method may involve receiving first electrode layer signals, corresponding to reflections of the first ultrasonic wave, from the electrode layer. The method may involve determining, based on the first electrode layer signals, a location of a target object in contact with the apparatus. The location of the target object may correspond with a proximate electrode element. The method may involve controlling the ultrasonic transceiver layer to transmit a second ultrasonic wave by sending second electrical signals to the proximate electrode element and for receiving receiver pixel signals from at least a portion of the plurality of ultrasonic receiver pixels in an area corresponding with the proximate electrode element.

Abstract: A method of controlling an apparatus that includes an ultrasonic sensor system may involve controlling the ultrasonic sensor system to transmit a first ultrasonic compressional wave and receiving first signals from the ultrasonic sensor system. The first signals may include signals corresponding to reflections of the first ultrasonic compressional wave from a target object proximate a surface of the apparatus. The method may involve performing an authentication process based, at least in part, on the first signals. The method may involve controlling the apparatus to transmit a shear wave and receiving second signals from the ultrasonic sensor system. The second signals may include signals corresponding to reflections of the shear wave from the target object. The method may involve performing a spoof detection process based, at least in part, on the second signals.

Abstract: An apparatus may include an ultrasonic sensor system, a low-frequency vibration source and a control system. The ultrasonic sensor system may include an ultrasonic receiver and an ultrasonic transmitter configured for transmitting ultrasonic waves in a first frequency range (e.g., 1 MHz to 30 MHz). The low-frequency vibration source may be configured for generating low-frequency vibrations in a second frequency range (e.g., the range of 5 Hz to 2000 Hz). The control system may be configured for synchronizing the generation of the first low-frequency vibrations and the transmission of the first ultrasonic waves.

Abstract: An apparatus may include an ultrasonic sensor system, a low-frequency vibration source and a control system. The ultrasonic sensor system may include an ultrasonic receiver and an ultrasonic transmitter configured for transmitting ultrasonic waves in a first frequency range (e.g., 1 MHz to 30 MHz). The low-frequency vibration source may be configured for generating low-frequency vibrations in a second frequency range (e.g., the range of 5 Hz to 2000 Hz). The control system may be configured for synchronizing the generation of the first low-frequency vibrations and the transmission of the first ultrasonic waves.

Abstract: Techniques described herein address these and other issues by providing an under-display sensor capable of providing fingerprint scanning over an entire display using optical and/or ultrasonic means. To do so, the sensor comprises an array of pixels, where each can pixel comprises a piezoelectric sensor element and a diode capable of being used as a photodetector during a light-sensing mode, and as a peak detector during a pressure-sensing mode. The sensor may further comprise a piezoelectric layer and one or more electrodes, which can generate a pressure wave during the pressure sensing mode.

Abstract: A device and method for improved sensing with a biometric sensor assembly such as an ultrasound fingerprint sensor using an anti-fingerprint, oleophobic, or hydrophobic coating applied to a surface above the biometric sensor assembly. The coating improves the mechanical coupling of a human finger to the surface, helping to reduce acoustic loss through the finger to surface interface, improving at least the false-rejection ratio.

Abstract: A device and method for producing said device comprising an improved ultrasonic biometric sensor is disclosed. The ultrasonic biometric sensor is composed of a pixel array and multiple copolymer layers which are polarized in such a fashion as to increase the transmitting pressure and receiving sensitivity of the sensor. The copolymer layers may be polarized in the same direction, or in opposite directions, depending on the desired functionality.

Abstract: An ultrasonic fingerprint sensor system of the present disclosure may be provided with a thick electrically nonconductive acoustic layer and thin electrode layer coupled to a piezoelectric layer of an ultrasonic transmitter or transceiver. The thick electrically nonconductive acoustic layer may have a high density or high acoustic impedance value, and may be adjacent to the piezoelectric layer. The thin electrode layer may be divided into electrode segments. The ultrasonic fingerprint sensor system may use flexible or rigid substrates, and may use an ultrasonic transceiver or an ultrasonic transmitter separate from an ultrasonic receiver.

Abstract: An ultrasonic fingerprint sensor system of the present disclosure may be provided with an ultrasonic transmitter or ultrasonic transceiver having an electrode layer divided into a plurality of electrode segments. The ultrasonic fingerprint sensor system may detect an object over one or more electrode segments and provide a voltage burst to one or more selected electrode segments for localized generation of ultrasonic waves. The localized generation of ultrasonic waves may facilitate localized readout for imaging. In some implementations, the voltage burst may be provided in a single-ended drive scheme or differential drive scheme.

Abstract: Techniques described herein address these and other issues by providing an under-display sensor capable of providing fingerprint scanning over an entire display using optical and/or ultrasonic means. To do so, the sensor comprises an array of pixels, where each can pixel comprises a piezoelectric sensor element and a diode capable of being used as a photodetector during a light-sensing mode, and as a peak detector during a pressure-sensing mode. The sensor may further comprise a piezoelectric layer and one or more electrodes, which can generate a pressure wave during the pressure sensing mode.

Abstract: An ultrasonic sensor array includes a plurality of ultrasonic transducers, each transducer including a piezoelectric member. Each of the transducers includes an electret member, a receive (Rx) layer configured to exhibit a first d33 resonating mode coefficient and a transmit (Tx) layer configured to exhibit a second d33 resonating mode coefficient, the first coefficient being different from the second coefficient. The transducers are disposed on a flexible substrate.

Abstract: An acoustic receiver system may be configured for receiving dynamic friction acoustic waves produced via relative motion between an outer surface of an apparatus and a target object in contact with the outer surface. A control system may be configured for receiving acoustic signals from the acoustic receiver system. The acoustic signals may correspond to a first instance of the dynamic friction acoustic waves. The control system may be configured for extracting target object features from the first acoustic signals and for performing an authentication process based, at least in part, on the target object features.

Abstract: Techniques for operating an ultrasonic sensor array, the ultrasonic sensor array disposed under a platen, include: making a determination whether or not to recalibrate the ultrasonic sensor array based on whether a first screen protector disposed above the platen has been removed or replaced by a second screen protector; and recalibrating the ultrasonic sensor array, when the determination is to recalibrate the ultrasonic sensor array. In some cases, the techniques include prompting a user to indicate whether or not the screen protector has been changed or removed, and recalibrating the ultrasonic sensor array only after confirmation from the user.

Abstract: An ultrasonic sensor includes a substrate, a platen and an acoustic stack disposed between the substrate and the platen, including at least one piezoelectric layer. The ultrasonic transducer exhibits a signal-to-noise ratio of at least 4 over a frequency range of at least 9 to 16 MHz.

Abstract: A stylus-tracking device may include a piezoelectric receiver or transceiver array on a first side (e.g., underneath) a display. Image data may be acquired from the piezoelectric receiver array. The image data may correspond to signals produced by the piezoelectric receiver array in response to an acoustic signal and/or a mechanical deformation caused by a target object (e.g., a stylus) in contact with a surface, such as a cover glass, proximate a second side of the display. A doublet pattern in the image data may include a first area of having signals below a threshold level and a second area having signals above the threshold level. Based on one or more doublet pattern characteristics, a position of the target object on the surface, a force of the target object on the surface and/or a first direction of movement of the target object relative to the surface may be estimated.

Abstract: The descried techniques may support a sensing scheme for reducing background signals in imaging sensors. A device may include a sensor configured to determine ridges and valleys of a fingerprint. The sensor may include a pixel array with each pixel of the pixel array having a set of electrodes. To reduce the background signals, the device may sense, e.g., during a transmit mode, a first set of signals associated with the pixel array using at least one electrode of the set of electrodes, and sense, e.g., during a receive mode, a second set of signals associated with the pixel array using the at least one electrode. The device may reduce a background signal associated with the sensor according to the sensing of the first set of signals and the second set of signals.