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 system may include an ultrasonic transceiver layer, a thin-film transistor (TFT) layer proximate a first side of the ultrasonic transceiver layer, a frequency-splitting layer proximate a second side of the ultrasonic transceiver layer and a high-impedance layer proximate the frequency-splitting layer. The frequency-splitting layer may reside between the ultrasonic transceiver layer and the high-impedance layer. The high-impedance layer may have a higher acoustic impedance than the frequency-splitting layer.

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: Various aspects of the present disclosure relate generally to ultrasonic fingerprint sensor. In some aspects, a device may include a flexible display. The device may include an ultrasonic fingerprint sensor that is configured to transmit and receive an ultrasonic signal in an acoustic path through the flexible display. The device may include an acoustics configuration layer that is situated between the display and the ultrasonic fingerprint sensor. The acoustics configuration layer may be configured to optimize a signal strength of the ultrasonic signal based at least in part on a configuration of one or more layers of the flexible display.

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: Certain aspects of the present disclosure provide techniques for selectively activating a fingerprint sensor in an electronic device. A method that may be performed by the electronic device includes detecting a finger hover above the display module, activating the fingerprint sensor based, at least in part, on the detected finger hover, and providing, in response to detecting the finger hover, feedback information to assist in scanning the finger using the fingerprint sensor.

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 ultrasonic sensor system may include an ultrasonic transceiver layer, a thin-film transistor (TFT) layer proximate a first side of the ultrasonic transceiver layer, a frequency-splitting layer proximate a second side of the ultrasonic transceiver layer and a high-impedance layer proximate the frequency-splitting layer. The frequency-splitting layer may reside between the ultrasonic transceiver layer and the high-impedance layer. The high-impedance layer may have a higher acoustic impedance than the frequency-splitting layer.

Abstract: Certain aspects of the present disclosure provide techniques for beamforming pressure waves. A method for operating an apparatus configured to beamform ultrasonic pressure waves may generally comprise emitting, via a pressure wave module of the apparatus, beamformed ultrasonic pressure waves through a display module of the apparatus, wherein: the display module comprises a first plurality of layers; the pressure wave module comprises a second plurality of layers; the second plurality of layers comprises at least a copolymer layer, a conductive layer, a dielectric protection layer, and a thin film transistor (TFT) glass layer; and an order of the second plurality of layers in the pressure wave module depends on an acoustic resonance value associated with the display module.

Abstract: Certain aspects of the present disclosure provide techniques for selectively activating a fingerprint sensor in an electronic device. A method that may be performed by the electronic device includes detecting a finger hover above the display module, activating the fingerprint sensor based, at least in part, on the detected finger hover, and providing, in response to detecting the finger hover, feedback information to assist in scanning the finger using the fingerprint sensor.

Abstract: A mobile device includes one or more piezoelectric polymer layers underlying a display. The one or more piezoelectric polymer layers may be electrically driven to operate in either a d33 stretching mode or a d31 bending mode. The mobile device functions as an ultrasonic sensor in the d33 stretching mode and as an audio speaker/microphone or a proximity sensor in the d31 bending mode. The piezoelectric polymer layer operating in the d31 bending mode may be directly mechanically coupled to a display, indirectly mechanically coupled to the display and underlying an ultrasonic sensor stack, or integrated in the ultrasonic sensor stack. Signal performance of the piezoelectric polymer layer operating in the d31 bending mode may be enhanced or modulated by having a larger area, multiple layers, bi-pole or uni-pole driving with multiple layers, one or more stiff adhesives, a spacer layer, one or more mass features, a thin TFT layer, a thick piezoelectric polymer layer, or combinations thereof.

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 example method of operation may include detecting a user touch in a first area based upon sensor data from one or more sensors of a first type, waking up one or more sensors of a second type configured to measure across some or all of the first area in response to the detecting, obtaining additional sensor data from the one or more sensors of the second type, and determining a location associated with the user touch based in part upon the sensor data from the one or more sensors of the second type.

Abstract: An example method of operation may include detecting a user touch in a first area based upon sensor data from one or more sensors of a first type, waking up one or more sensors of a second type configured to measure across some or all of the first area in response to the detecting, obtaining additional sensor data from the one or more sensors of the second type, and determining a location associated with the user touch based in part upon the sensor data from the one or more sensors of the second type.

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: A method may involve estimating a force applied by a target object on a surface, determining at least one ultrasonic fingerprint sensor parameter modification based, at least in part, on the force and updating at least one setting of an ultrasonic fingerprint sensor based, at least in part, on the ultrasonic fingerprint sensor parameter modification. The method may involve controlling the ultrasonic fingerprint sensor to transmit first and second ultrasonic waves towards the target object and receiving first and second ultrasonic receiver signals, including signals corresponding to reflections of the first and second ultrasonic waves from the target object, from the ultrasonic fingerprint sensor. The method may involve performing an authentication process based, at least in part, on the first and second ultrasonic receiver signals.

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 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.