公开(公告)号：US12184973B2

公开(公告)日：2024-12-31

申请号：US18177668

申请日：2023-03-02

Applicant: OMNIVISION TECHNOLOGIES, INC.

Inventor： Wenlei Yang ,  Shoushun Chen ,  Andreas Suess

IPC: H04N23/60 ,  H04N25/707 ,  H04N25/772

Abstract: Methods for transmitting asynchronous event data via synchronous communications interfaces (and associated imaging systems) are disclosed herein. In one embodiment, an imager comprises an array of event vision pixels, a synchronous communications transmitter configured to transmit frames of data to a synchronous communications receiver, and a timer configured to indicate when a threshold amount of time has elapsed. The pixels can generate event data based on activity within an external scene. The imager can be configured to insert available event data into a payload of the current frame during a first time period before the frame timer indicates that the threshold amount of time has elapsed, pad the payload with dummy data during a second time period after the frame timer indicates that the threshold amount of time has elapsed, and transmit (using the synchronous communications transmitter) the current frame of data to the synchronous communications receiver.

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.

公开(公告)号：US11516419B2

公开(公告)日：2022-11-29

申请号：US17156290

申请日：2021-01-22

Applicant: OMNIVISION TECHNOLOGIES, INC.

Inventor： Tiejun Dai ,  Shoushun Chen ,  Zhe Gao

IPC: H04N5/3745 ,  H01L27/146 ,  H04N5/345 ,  H04N5/355 ,  H04N5/378

Abstract: An event driven pixel includes a photodiode configured to photogenerate charge in response to incident light received from an external scene. A photocurrent to voltage converter is coupled to the photodiode to convert photocurrent generated by the photodiode to a voltage. A filter amplifier is coupled to the photocurrent to voltage converter to generate a filtered and amplified signal in response to the voltage received from the photocurrent to voltage converter. A threshold comparison stage is coupled to the filter amplifier to compare the filtered and amplified signal received from the filter amplifier with thresholds to asynchronously detect events in the external scene in response to the incident light. A digital time stamp generator is coupled to asynchronously generate a digital time stamp in response to the events asynchronously detected in the external scene by the threshold comparison stage.