Qualcomm Incorporated

University of California

Yipeng Lu

Hrishikesh Vijaykumar Panchawagh

Jessica Liu Strohmann

Kostadin Dimitrov Djordjev

David William Burns

Hao-Yen Tang

Nicholas Ian Buchan

Nai-Kuei Kuo

Suryaprakash Ganti

David Horsley

Bernhard Boser

Shiang-Chi Lin

Ravindra Vaman Shenoy

John Keith Schneider

Jack Conway Kitchens

Chin-Jen Tseng

Jae Hyeong Seo

Yair Karmi

Tsongming Kao

Chia-Wei Yang

Min-Lun Yang

Ali Lopez

Jon Lasiter

Firas Sammoura

Sameer Wadhwa

Yue Liang

Timothy Dickinson

Sandeep Louis D'Souza

Raj Kumar

Donald William Kidwell, Jr

Sai Praneeth Sreeram

Stephen Michael Gojevic

Fitzgerald John Archibald

Jack Conway Kitchens, Ii

Ashish Hinger

Evan Michael Breloff

Leonard Eugene Fennell

Alexei Stoianov

Changting Xu

James Anthony Miranto

Soon Joon Yoon

Emily Kathryn Brooks

Ila Ravindra Badge

Nirma Lnu

Yuri Kusano

Jon Bradley Lasiter

Timothy Alan Dickinson

Donald William Kidwell Jr

Some disclosed implementations include an ultrasonic sensor stack and an acoustic resonator. The acoustic resonator may be configured to enhance ultrasonic waves transmitted by the ultrasonic sensor stack in an ultrasonic frequency range that is suitable for ultrasonic fingerprint sensors. In some examples, the acoustic resonator may include one or more low-impedance layers residing between a first higher-impedance layer and a second higher-impedance layer. Each of the one or more low-impedance layers may have a lower acoustic impedance than an acoustic impedance of the first higher-impedance layer or an acoustic impedance of the second higher-impedance layer. At least one low-impedance layer may have a thickness corresponding to a multiple of a half wavelength at a peak frequency of the acoustic resonator. The peak frequency may be within a frequency range from 1 MHz. to 20 MHz.

Apparatus with ultrasonic fingerprint sensor and one or more resonators, and related systems and methods

Disclosed are methods, devices, apparatuses, and systems for an under-display ultrasonic fingerprint sensor. A display device may include a platen, a display underlying the platen, and an ultrasonic fingerprint sensor underlying the display, where the ultrasonic fingerprint sensor is configured to transmit and receive ultrasonic waves via an acoustic path through the platen and the display. A light-blocking layer and/or an electrical shielding layer may be provided between the ultrasonic fingerprint sensor and the display, where the light-blocking layer and/or the electrical shielding layer are in the acoustic path. A mechanical stress isolation layer may be provided between the ultrasonic fingerprint sensor and the display, where the mechanical stress isolation layer is in the acoustic path.

Ultrasonic fingerprint sensor for under-display applications

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.

Audio speaker and proximity sensor with piezoelectric polymer technology

An apparatus may include an ultrasonic sensor stack, a foldable display stack and a transmission enhancement layer. The foldable display stack may include a display stiffener and display stack layers. The display stack layers may form one or more display stack resonators configured to enhance ultrasonic waves transmitted by the ultrasonic sensor stack in a first ultrasonic frequency range. In some implementations, a transmission enhancement resonator may include the display stiffener and the transmission enhancement layer. In some examples, the transmission enhancement resonator may include at least a portion of the ultrasonic sensor stack. The transmission enhancement resonator may be configured to enhance the ultrasonic waves transmitted by the ultrasonic sensor stack in the first ultrasonic frequency range.

Under-display ultrasonic fingerprint sensors for foldable displays

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. Numerous other aspects are provided

Configuration of an ultrasonic fingerprint sensor relative to a display of a device

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.

Ultrasonic sensor array control to facilitate screen protectors

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.

Ultrasonic sensor array

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.

Ultrasonic sensor system with higher-frequency and lower-frequency areas

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.

Broadband ultrasonic sensor

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.

Multiple-frequency ultrasonic sensor system

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.

Growing community of inventors

Davis, CA, United States of America

Yipeng Lu