公开(公告)号：US11770633B2

公开(公告)日：2023-09-26

申请号：US17513064

申请日：2021-10-28

Applicant: OMNIVISION TECHNOLOGIES, INC.

Inventor： Andreas Suess ,  Zheng Yang

IPC: H04N25/75 ,  H01L27/148 ,  H01L27/146 ,  H04N25/71 ,  G01S17/894

CPC classification number: H04N25/75 ,  G01S17/894 ,  H01L27/14612 ,  H01L27/14831 ,  H04N25/745

Abstract: A time-of-flight sensor includes a pixel array of pixel circuits. A first subset of the pixel circuits is illuminated by reflected modulated light from a portion of an object. A second subset of the pixel circuits is non-illuminated by the reflected modulated light. Each pixel circuit includes a floating diffusion that stores a portion of charge photogenerated in a photodiode in response to the reflected modulated light. A transfer transistor transfers the portion of charge from the photodiode to the floating diffusion in response to modulation by a phase modulation signal. A modulation driver block generates the phase modulation signal and is coupled to a light source that emits the modulated light to the portion of the object. The modulation driver block synchronizes scanning the modulated light emitted by the light source across the object with scanning of the first subset of the pixel circuits across the pixel array.

公开(公告)号：US11729534B1

公开(公告)日：2023-08-15

申请号：US17875240

申请日：2022-07-27

Applicant: OMNIVISION TECHNOLOGIES, INC.

Inventor： Andreas Suess ,  Shoushun Chen

IPC: H04N25/772 ,  H04N25/42 ,  H04N25/50 ,  H04N25/709 ,  H03K19/00 ,  H03K19/20 ,  H03M1/40 ,  H03M1/44

CPC classification number: H04N25/772 ,  H04N25/42 ,  H04N25/50 ,  H04N25/709

Abstract: Low power event driven pixels with passive difference detection circuit (and reset control circuits for the same) are disclosed herein. In one embodiment, an event driven pixel comprises a photosensor; a photocurrent-to-voltage converter, and a difference circuit. The difference circuit includes a source follower transistor and a switched-capacitor filter having an input coupled to the photocurrent-to-voltage converter and an output coupled to a gate of the source follower transistor. The switched-capacitor filter includes a first capacitor coupled between the input and the output of the switched-capacitor filter, a second capacitor having a first plate coupled to the output of the switched-capacitor filter, and a reset transistor coupled between a reference voltage and the output of the switched-capacitor filter. The difference circuit is configured generate a difference signal that is indicative of whether the event driven pixel has detected an event in an external scene.