Abstract: An apparatus may include an ultrasonic sensor system having an ultrasonic transceiver layer, a thin-film transistor (TFT) layer and a frequency-differentiating layer. In some examples, the frequency-differentiating layer may include a first frequency-differentiating layer area corresponding to a lower-frequency area of the ultrasonic sensor system. The first frequency-differentiating layer area may include a first material having a first acoustic impedance. In some such examples, the frequency-differentiating layer may include a second frequency-differentiating layer area corresponding to a higher-frequency area of the ultrasonic sensor system. The second frequency-differentiating layer area may include a second material having a second acoustic impedance. The first acoustic impedance may, for example, be higher than the second acoustic impedance.

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: 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: 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: Some disclosed methods involve acquiring, via an ultrasonic sensor system, first (reference) ultrasonic signals at a first time and acquiring second ultrasonic signals via the ultrasonic sensor system at a second time. Such methods may involve determining, based at least in part on a comparison of the first ultrasonic signals and the second ultrasonic signals, whether one or more layers reside on the cover glass at the second time. If it is determined that the one or more layers reside on the cover glass at the second time, some methods may involve determining one or more signal characteristics corresponding to properties of the one or more layers and determining, based at least in part on the one or more properties, whether the one or more layers are compatible with the ultrasonic sensor system. If so, the method may involve calibrating the ultrasonic sensor system.

Abstract: An apparatus may include an ultrasonic sensor system, a Coulomb force apparatus and a control system. The control system may be configured for controlling the Coulomb force apparatus for application of a Coulomb force to a digit in contact with an outer surface of the apparatus in a fingerprint sensor area and for controlling the ultrasonic fingerprint sensor for transmission of first ultrasonic waves towards the digit. The control system may be configured for synchronizing the application of the Coulomb force and the transmission of the first ultrasonic waves. The control system may be configured for receiving ultrasonic receiver signals from the ultrasonic fingerprint sensor and for performing an authentication process based, at least in part, on the ultrasonic receiver signals. The ultrasonic receiver signals may, in some instances, include signals corresponding to reflections of the first ultrasonic waves from the digit.

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: Some disclosed methods involve acquiring, via an ultrasonic sensor system, first (reference) ultrasonic signals at a first time and acquiring second ultrasonic signals via the ultrasonic sensor system at a second time. Such methods may involve determining, based at least in part on a comparison of the first ultrasonic signals and the second ultrasonic signals, whether one or more layers reside on the cover glass at the second time. If it is determined that the one or more layers reside on the cover glass at the second time, some methods may involve determining one or more signal characteristics corresponding to properties of the one or more layers and determining, based at least in part on the one or more properties, whether the one or more layers are compatible with the ultrasonic sensor system. If so, the method may involve calibrating the ultrasonic sensor system.

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: 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 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 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 Coulomb force apparatus and a control system. The control system may be configured for controlling the Coulomb force apparatus for application of a Coulomb force to a digit in contact with an outer surface of the apparatus in a fingerprint sensor area and for controlling the ultrasonic fingerprint sensor for transmission of first ultrasonic waves towards the digit. The control system may be configured for synchronizing the application of the Coulomb force and the transmission of the first ultrasonic waves. The control system may be configured for receiving ultrasonic receiver signals from the ultrasonic fingerprint sensor and for performing an authentication process based, at least in part, on the ultrasonic receiver signals. The ultrasonic receiver signals may, in some instances, include signals corresponding to reflections of the first ultrasonic waves from the digit.

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 ultrasonic fingerprint sensor system of the present disclosure may be provided with a flexible substrate. The ultrasonic fingerprint sensor system may include a film stack disposed on the flexible substrate that provides acceptable acoustic coupling for fingerprint sensing. The ultrasonic fingerprint sensor system includes a high acoustic impedance layer in an acoustic path of ultrasonic waves through a display. The high acoustic impedance layer can be electrically conductive or electrically nonconductive. In some implementations, the ultrasonic fingerprint sensor system includes an ultrasonic transceiver or an ultrasonic transmitter separate from an ultrasonic receiver.

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 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.