公开(公告)号：US11460957B2

公开(公告)日：2022-10-04

申请号：US17195465

申请日：2021-03-08

Applicant: InvenSense, Inc.

Inventor： Mark Jennings ,  Mei-Lin Chan

IPC: G06F3/043 ,  G06F3/041 ,  H01L41/047 ,  H01L41/083 ,  G06V40/13

Abstract: 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 configured to activate different subsets of ultrasonic transducers associated with different regions of the two-dimensional array of ultrasonic transducers at different transmission frequencies, where the different frequencies are determined such that a thickness of the matching layer at a region is substantially equal to a quarter wavelength of the first transmission frequency for the region. The array controller is also configured to combine the plurality of pixels into a compound fingerprint image that compensates for the non-uniform thickness of the matching layer.

公开(公告)号：US11243300B2

公开(公告)日：2022-02-08

申请号：US16814917

申请日：2020-03-10

Applicant: InvenSense, Inc.

Inventor： Mark Jennings ,  Romain Fayolle ,  Amaury Robles ,  Pierre Peiffer

IPC: G06K9/28 ,  G06K9/36 ,  G01S7/52 ,  G06K9/00 ,  G06K9/32

Abstract: 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 transducers for determining whether the object is a human finger, where the subset of ultrasonic transducers is proximate the presence sensor such that the subset of ultrasonic transducers and the presence sensor can concurrently interact with the object.