OPERATION OF AN ULTRASONIC SENSOR
Granted: December 23, 2021
Application Number:
20210396718
In a method of using an ultrasonic sensor comprising a two-dimensional array of ultrasonic transducers, a plurality of ultrasonic signals are transmitted according to a beamforming pattern at a position of the two-dimensional array. The beamforming pattern focuses the plurality of ultrasonic signals to location above the two-dimensional array, wherein the beamforming pattern identifies ultrasonic transducers of the two-dimensional array that are activated during transmission of the…
PRESSURE-BASED ACTIVATION OF FINGERPRINT SPOOF DETECTION
Granted: October 28, 2021
Application Number:
20210334568
In a method for performing operating a fingerprint sensor, an image of a fingerprint of a finger is captured at a fingerprint sensor. A force applied by the finger at the fingerprint sensor is determined, where the force is a measure of pressure applied by the finger on the fingerprint sensor during capture of the image. The force is compared to a pressure threshold. Provided the force satisfies a pressure threshold, a spoof detection operation is performed to determine whether the…
OPERATING A FINGERPRINT SENSOR COMPRISED OF ULTRASONIC TRANSDUCERS AND A PRESENCE SENSOR
Granted: September 16, 2021
Application Number:
20210286060
In a method for operating a fingerprint sensor including a plurality of ultrasonic transducers and a presence sensor, the presence sensor proximate the fingerprint sensor is activated, where the presence sensor is for detecting interaction between an object and the fingerprint sensor. Subsequent to detecting interaction between an object and the fingerprint sensor at the presence sensor, a subset of ultrasonic transducers of the fingerprint sensor is activated, the subset of ultrasonic…
ULTRASONIC FINGERPRINT SENSOR WITH A CONTACT LAYER OF NON-UNIFORM THICKNESS
Granted: September 9, 2021
Application Number:
20210278927
An ultrasonic sensor includes a two-dimensional array of ultrasonic transducers, a contact layer, a matching layer between the two-dimensional array and the contact layer, where the matching layer has a non-uniform thickness, and an array controller configured to control activation of ultrasonic transducers during an imaging operation for imaging a plurality of pixels within the two-dimensional array of ultrasonic transducers. During the imaging operation, the array controller is…
OPERATING A FINGERPRINT SENSOR COMPRISED OF ULTRASONIC TRANSDUCERS
Granted: April 29, 2021
Application Number:
20210124892
In a method for operating a fingerprint sensor including a plurality of ultrasonic transducers, receiving a plurality of images corresponding to different subsets of the ultrasonic transducers of the fingerprint sensor are received, wherein the plurality of images are non-adjacent. For each image of the plurality of images, it is determined whether the image of the plurality of images is indicative of a fingerprint. Provided a number of images of the plurality of images that are…
FINGERPRINT AUTHENTICATION USING A SYNTHETIC ENROLLMENT IMAGE
Granted: April 22, 2021
Application Number:
20210117721
In a method for fingerprint authentication, a fingerprint image is received from a fingerprint sensor. Fingerprint authentication of the fingerprint image is performed by comparing the fingerprint image to a set of authentication fingerprint images including at least one enrollment fingerprint image and at least one transformed fingerprint image, where the transformed fingerprint image is generated by applying a transfer function to at least one enrollment fingerprint image of the set of…
DETERMINATION OF BLOOD VESSEL CHARACTERISTIC CHANGE USING AN ULTRASONIC SENSOR
Granted: April 8, 2021
Application Number:
20210100523
In a method for determining blood vessel characteristic change using an ultrasonic sensor, a plurality of ultrasonic signal transmit and receive operations are performed at a position overlying a blood vessel of a person using an ultrasonic sensor, where the plurality of ultrasonic signal transmit and receive operations generate a plurality of received signals. Depths of blood vessel walls are determined at the position for a plurality of time instances based on local maxima of a…
SYSTEM AND METHOD FOR FINGERPRINT AUTHENTICATION
Granted: April 1, 2021
Application Number:
20210097257
A fingerprint authentication system includes a fingerprint imaging sensor and a spoof detector sensor. The fingerprint imaging sensor includes a two-dimensional array of ultrasonic transducers, where the fingerprint imaging sensor is for capturing an image of a fingerprint of a finger. The spoof detector sensor includes at least one ultrasonic transducer, where the spoof detector sensor is for capturing data used to determine whether the finger is a real finger. A contact layer overlies…
MEMS DEVICE WITH REDUCED ELECTRIC CHARGE, CAVITY VOLUME AND STICTION
Granted: March 11, 2021
Application Number:
20210070608
A method includes forming a first mask on a first portion of a first surface of a substrate, forming a second mask on the first mask and further forming the second mask on a second portion of the first surface of the substrate, and etching an exposed portion of the first surface of the substrate and removing the second mask. According to some embodiments, an exposed portion of the first surface of the substrate is etched and the first mask is removed. An oxide layer is formed on the…
ADAPTING A QUALITY THRESHOLD FOR A FINGERPRINT IMAGE
Granted: February 25, 2021
Application Number:
20210056673
In a method for adapting a quality threshold for a fingerprint image, a fingerprint image is received. An image quality of the fingerprint image is determined. Provided the image quality of the fingerprint image does not satisfy a quality threshold, the quality threshold is decreased. Provided the image quality of the fingerprint image does satisfy a decreased quality threshold, the fingerprint image is forwarded to a matcher for fingerprint authentication.
ULTRASONIC FINGERPRINT SENSOR WITH A CONTACT LAYER OF NON-UNIFORM THICKNESS
Granted: January 21, 2021
Application Number:
20210019488
An ultrasonic sensor includes a two-dimensional array of ultrasonic transducers, wherein the two-dimensional array of ultrasonic transducers is substantially flat, a contact layer having a non-uniform thickness overlying the two-dimensional array of ultrasonic transducers, and an array controller configured to control activation of ultrasonic transducers during an imaging operation. During the imaging operation, the array controller is configured to control a transmission frequency of…
ULTRASONIC FINGERPRINT SENSOR WITH A CONTACT LAYER OF NON-UNIFORM THICKNESS
Granted: January 21, 2021
Application Number:
20210019487
An ultrasonic sensor includes a two-dimensional array of ultrasonic transducers, wherein the two-dimensional array of ultrasonic transducers is substantially flat, a contact layer having a non-uniform thickness overlying the two-dimensional array of ultrasonic transducers, and an array controller configured to control activation of ultrasonic transducers during an imaging operation for imaging a plurality of pixels at a plurality of positions within the two-dimensional array of…
FAKE FINGER DETECTION BASED ON TRANSIENT FEATURES
Granted: December 31, 2020
Application Number:
20200410268
In a method for determining whether a finger is a real finger at an ultrasonic fingerprint sensor, a sequence of images of a fingerprint of a finger are captured at an ultrasonic fingerprint sensor, wherein the sequence of images includes images captured during a change in contact state between the finger and the ultrasonic fingerprint sensor. A plurality of transient features of the finger is extracted from the sequence of images. A classifier is applied to the plurality of transient…
FAKE FINGER DETECTION USING RIDGE FEATURES
Granted: December 24, 2020
Application Number:
20200401783
In a method for determining whether a finger is a real finger at an ultrasonic fingerprint sensor, a first image of a fingerprint pattern is captured at an ultrasonic fingerprint sensor, wherein the first image is based on ultrasonic signals corresponding to a first time of flight range. A second image of the fingerprint pattern is captured at the ultrasonic fingerprint sensor, wherein the second image is based on ultrasonic signals corresponding to a second time of flight range, the…
PIEZOELECTRIC MICROMACHINED ULTRASONIC TRANSDUCER (PMUT)
Granted: December 24, 2020
Application Number:
20200400800
A Piezoelectric Micromachined Ultrasonic Transducer (PMUT) device is provided. The PMUT includes a substrate and an edge support structure connected to the substrate. A membrane is connected to the edge support structure such that a cavity is defined between the membrane and the substrate, where the membrane is configured to allow movement at ultrasonic frequencies. The membrane includes a piezoelectric layer and first and second electrodes coupled to opposing sides of the piezoelectric…
DUAL LAYER ULTRASONIC TRANSDUCER
Granted: November 26, 2020
Application Number:
20200367858
An ultrasonic transducer device including a substrate, an edge support structure connected to the substrate, and a membrane connected to the edge support structure such that a cavity is defined between the membrane and the substrate, the membrane configured to allow movement at ultrasonic frequencies. The membrane includes a first piezoelectric layer having a first surface and a second surface, a second piezoelectric layer having a first surface and a second surface, wherein the second…
TRANSMIT BEAMFORMING OF A TWO-DIMENSIONAL ARRAY OF ULTRASONIC TRANSDUCERS
Granted: November 12, 2020
Application Number:
20200357379
In a method for transmit beamforming of a two-dimensional array of ultrasonic transducers, a beamforming pattern to apply to a beamforming space of the two-dimensional array of ultrasonic transducers is defined. The beamforming space includes a plurality of elements, where each element of the beamforming space corresponds to an ultrasonic transducer of the two-dimensional array of ultrasonic transducers, where the beamforming pattern identifies which ultrasonic transducers within the…
OPERATING A TWO-DIMENSIONAL ARRAY OF ULTRASONIC TRANSDUCERS
Granted: November 12, 2020
Application Number:
20200355824
In a method of operating a two-dimensional array of ultrasonic transducers, a plurality of array positions comprising pluralities of ultrasonic transducers of the two-dimensional array of ultrasonic transducers is defined, the plurality of array positions each comprising a portion of ultrasonic transducers of the two dimensional array of ultrasonic transducers. For each array position of the plurality of array positions, a plurality of ultrasonic transducers associated with the…
METHOD AND SYSTEM FOR SENSOR CONFIGURATION
Granted: November 5, 2020
Application Number:
20200348134
Described herein are methods and systems for configuring a motion sensor assembly to compensate for a temperature gradient. First and second sensors of the same type are arranged as opposing pairs with respect to a first axis that may be defined by a temperature gradient caused by at least one thermal element. Combining the output measurements of the first sensor and the second sensor allows effects of the temperature gradient on sensor measurements of the first sensor and the second…
METHOD AND SYSTEM FOR SENSOR CONFIGURATION
Granted: November 5, 2020
Application Number:
20200348189
Described herein are methods and systems for configuring sensors to compensate for a temperature gradient. Multiple sensor sets, each having at least two sensors of a same type with orthogonal axes, are positioned to form at least one opposing sensor pair, in which an axis of one sensor of one sensor set is in an opposite orientation to an axis of one sensor of another sensor set. A combined measurement of each opposing sensor pair may be output which is compensated for an effect of a…
