Qualcomm Incorporated

Jessica Liu Strohmann

Hrishikesh Vijaykumar Panchawagh

Yipeng Lu

Kostadin Dimitrov Djordjev

Chin-Jen Tseng

David William Burns

Nicholas Ian Buchan

Shiang-Chi Lin

Changting Xu

Soon Joon Yoon

Min-Lun Yang

Chia-Wei Yang

Sandeep Louis D'Souza

Nai-Kuei Kuo

Jae Hyeong Seo

Yair Karmi

Ali Lopez

Kwokleung Chan

Raj Kumar

Firas Sammoura

Leonard Eugene Fennell

Ila Ravindra Badge

Mario Francisco Velez

Suryaprakash Ganti

Yue Liang

Chun Yiu Chu

Hasib Siddiqui

Suzana Arellano

Jin Gu

Ashish Hinger

Lior Maor

Javier Frydman

Gal Rotem

Sherman Sebastian Antao

Tsongming Kao

Deepak Rajendra Karnik

Jon Gregory Aday

Mowen Yang

Efthymios Philip Papageorgiou

Bernard Herrera

Yuri Kusano

Shaojui Li

Jorge Adrian Madrigal Ramirez

Advait Prasad Koparkar

Wei-En Hsu

Hsiang-Chi Liu

Chuenwen Chung

An apparatus for common mode noise cancellation in an ultrasonic fingerprint sensor comprising a resistor-inductor-capacitor (RLC) network, a piezoelectric layer, a pixel array electrically coupled with the RLC network at a first end of the RLC network and either: (A) a common mode canceling capacitive element electrically coupled with the RLC network in parallel with the pixel array and configured to attenuate at least a portion of the common mode component from the acoustic signal before the acoustic signal is received by the pixel array or (B) a common mode canceling circuitry electrically coupled with the RLC network at a second end of the RLC network and configured to introduce a feedback signal to the pixel array through the RLC network, wherein the feedback signal is determined based on the received acoustic signal at each pixel within the pixel array.

Ultrasonic fingerprint sensor with passive and active common mode cancellation

Some methods may involve receiving fingerprint image data. Some methods may involve determining whether the fingerprint image data was captured by a first fingerprint sensor of a device or a second fingerprint sensor of the device. Some methods may involve obtaining an enhanced version of the fingerprint image data based on a determination that the fingerprint image data was captured by the second fingerprint sensor of the device. Some methods may involve providing the enhanced version of the fingerprint image data for authentication. In some examples, obtaining the enhanced version of the fingerprint image data may involve an image enhancement machine learning model. In some examples, prior to obtaining the enhanced version of the fingerprint image data, a determination is made that the fingerprint image data captured by the second fingerprint sensor fails to satisfy a quality threshold.

Image enhancement for fingerprint sensor deployed in a flexible device

An apparatus may include a display stack, an ultrasonic sensor stack and a high-impedance stack including one or more high-impedance layers. The ultrasonic sensor stack may include an ultrasonic transceiver layer and an ultrasonic transceiver circuitry (UTC) layer. Each of the high-impedance layers may have an acoustic impedance that is higher than an acoustic impedance of the UTC layer. The high-impedance stack and the ultrasonic sensor stack may form an acoustic resonator bounded by the UTC layer and the high-impedance stack. The acoustic resonator may be configured to enhance the ultrasonic waves transmitted by the ultrasonic sensor stack at a peak frequency of the ultrasonic sensor stack. The peak frequency may be a frequency used by the ultrasonic sensor stack for obtaining fingerprint images. An apparatus stack portion that includes the ultrasonic sensor stack may have a thickness corresponding to a multiple of a quarter wavelength at the peak frequency.

Devices including one or more high-impedance layers between a display stack and an ultrasonic fingerprint sensor stack

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

Some methods may involve receiving fingerprint image data and a first set of background image data from a fingerprint sensor and determining first processed fingerprint image data via a subtraction of the first set of background image data from the fingerprint image data. Some methods may involve obtaining force data corresponding to a force applied to the fingerprint sensor when the fingerprint image data were obtained. Some methods may involve obtaining a second set of background image data corresponding to the force data. Some methods may involve determining second processed fingerprint image data based, at least in part, on the first processed fingerprint image data and the second set of background image data, and outputting the second processed fingerprint image data. In some examples, determining the second processed fingerprint image data may involve a machine learning model. Some examples may involve estimating residual noise based on the force data.

Image compensation for fingerprint sensor deployed in a flexible device

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

An apparatus includes an ultrasonic sensor stack, a foldable display stack that includes a display stiffener, and an additional stiffener between the ultrasonic sensor stack and the foldable display stack. The additional stiffener forms an acoustic resonator with the display stiffener and an adhesive layer between the display stiffener and the additional stiffener in order to amplify transmission of ultrasonic waves transmitted by the ultrasonic sensor stack. The additional stiffener includes a material having a high modulus of elasticity, low density, and high acoustic impedance value. In some cases, the additional stiffener includes a metal, a ceramic, a glass, or a glass ceramic. The additional stiffener increases an overall stiffness and mechanical integrity of the apparatus so that a foam backer may be omitted from the ultrasonic sensor stack.

Ultrasonic sensor system and multi-layer stiffener for foldable display

Some disclosed devices may include a display stack, a cover layer proximate a first side of the display stack and a segmented transducer array proximate a second side of the display stack. The segmented transducer array may include a plurality of separate transducer segments. Each of the separate transducer segments may include a piezoelectric layer and a thin-film transistor (TFT) layer. The separate transducer segments may include transmitter transducer segments and receiver transducer segments. In some examples, a spacing between at least a first plurality of the transmitter transducer segments may correspond to a display stack and cover layer oscillation mode frequency in a range from 20 Hz to 20 kHz, from 15 kHz to 200 kHz or from 20 kHz to 400 kHz.

Segmented transducers for acoustic applications

Growing community of inventors

Cupertino, CA, United States of America

Jessica Liu Strohmann