# US 12,192,655 B2 · Time delay integration sensor handling defect pixels > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,192,655 B2 - Document ID: US12192655B2 - Status: Granted - Kind: B2 - Application number: 18/503,265 - Filed: 2023-11-07 - Published: 2024-02-29 - Granted: 2025-01-07 - Earliest claimed: 2021-10-15 - Assignees: Pixart Imaging Inc.; Taiwan Space Agency - Applicants: Pixart Imaging Inc.; Taiwan Space Agency - Inventors: Ren-Chieh Liu; Chao-Chi Lee; Yi-Yuan Chen; En-Feng Hsu - Web page: https://patentgrep.com/patent/US12192655B2 ## CPC - H04N 25/683: by defect estimation performed on the scene signal, e.g. real time or on the fly detection - H04N 25/768: for time delay and integration [TDI] - H04N 25/531: by controlling rolling shutters in CMOS SSIS - H04N 25/75: Circuitry for providing, modifying or processing image signals from the pixel array - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION ## Abstract The present disclosure provides a time delay integration (TDI) sensor using a rolling shutter. The TDI sensor includes multiple pixel columns. Each pixel column includes multiple pixels arranged in an along-track direction, wherein two adjacent pixels or two adjacent pixel groups in every pixel column have a separation space therebetween. The separation space is equal to a pixel height multiplied by a time ratio of a line time difference of the rolling shutter and a frame period, or equal to a summation of at least one pixel height and a multiplication of the pixel height by the time ratio of the line time difference and the frame period. The TDI sensor further records defect pixels of a pixel array such that in integrating pixel data to integrators, the pixel data associated with the defect pixels is not integrated into corresponding integrators. ## Claims ### Claim 1 A time delay integration (TDI) image sensor, configured to capture an image frame using a rolling shutter and move with respect to a scene in an along-track direction, the image sensor comprising: a pixel array, comprising multiple pixel columns, each of the pixel columns comprising multiple pixels arranged in the along-track direction, and two adjacent pixels of each of the pixel columns having a separation space therebetween, wherein the multiple pixels of each of the pixel columns comprise multiple normal pixels and at least one reserved pixel, and the separation space comprises a multiplication of a pixel height in the along-track direction by a time ratio of a line time difference of the rolling shutter and a frame period of capturing the image frame; and multiple integrators, respectively coupled to the multiple pixel columns, and each of the multiple integrators being configured to integrate pixel data of the multiple normal pixels at a corresponding pixel column, wherein when the multiple normal pixels have a defect pixel, the integrator corresponding to a pixel column of the defect pixel integrates pixel data of the reserved pixel to replace pixel data of the defect pixel. ### Claim 2 (depends on 1) The image sensor as claimed in claim 1, wherein the line time difference is a time interval between a time of starting exposure of two adjacent pixel rows of the pixel array. ### Claim 3 (depends on 1) The image sensor as claimed in claim 1, further comprising a memory configured to record a pixel position of at least one defect pixel of the pixel array. ### Claim 4 (depends on 3) The image sensor as claimed in claim 3, wherein the pixel position of the at least one defect pixel is recorded before shipment or recorded in a test mode during operation. ### Claim 5 (depends on 1) The image sensor as claimed in claim 1, wherein the multiple integrators are respectively configured to integrate pixel data of a same position of the scene in adjacent image frames. ### Claim 6 (depends on 1) The image sensor as claimed in claim 1, further comprising a readout circuit and a reserved pixel row, wherein upon the multiple normal pixels having no defect pixel, the readout circuit is configured not to read pixel data of the reserved pixel row, and the readout circuit is configured to read the pixel data of the reserved pixel row only when the multiple normal pixels have at least one defect pixel. ### Claim 7 (depends on 1) The image sensor as claimed in claim 1, further comprising a readout circuit and a reserved pixel row, wherein upon the multiple normal pixels having no defect pixel, the readout circuit is configured to read pixel data of the reserved pixel row, but the pixel data of the reserved pixel row read by the readout circuit is not integrated into the multiple integrators. ### Claim 8 A time delay integration (TDI) image sensor, configured to capture an image frame using a rolling shutter and move with respect to a scene in an along-track direction, the image sensor comprising: a pixel array, comprising multiple pixel columns, each of the pixel columns comprising multiple pixels arranged in the along-track direction, and two adjacent pixels of each of the pixel columns having a separation space therebetween, wherein the separation space comprises a multiplication of a pixel height in the along-track direction by a time ratio of a line time difference of the rolling shutter and a frame period of capturing the image frame; and multiple integrators, respectively coupled to the multiple pixel columns, and each of the multiple integrators being configured to integrate pixel data of the multiple pixels at a corresponding pixel column, wherein when the multiple pixels have a defect pixel, the integrator corresponding to a pixel column of the defect pixel does not integrate pixel data of the defect pixel. ### Claim 9 (depends on 8) The image sensor as claimed in claim 8, wherein the multiple integrators are respectively configured to integrate pixel data of a same position of the scene in adjacent image frames. ### Claim 10 (depends on 8) The image sensor as claimed in claim 8, further comprising a memory configured to record a pixel position of at least one defect pixel of the pixel array. ### Claim 11 (depends on 10) The image sensor as claimed in claim 10, wherein the pixel position of the at least one defect pixel is recorded before shipment or recorded in a test mode during operation. ### Claim 12 A time delay integration (TDI) image sensor, configured to capture an image frame using a rolling shutter and move with respect to a scene in an along-track direction, the image sensor comprising: a pixel array, comprising multiple pixel columns, each of the pixel columns comprising multiple pixels arranged in the along-track direction, and two adjacent pixels of each of the pixel columns having a separation space therebetween, wherein the separation space comprises a multiplication of a pixel height in the along-track direction by a time ratio of a line time difference of the rolling shutter and a frame period of capturing the image frame; and multiple integrators, respectively coupled to the multiple pixel columns, and each of the multiple integrators being configured to integrate pixel data of the multiple pixels at a corresponding pixel column, wherein when the multiple pixels have a defect pixel, a first integration number of pixel data of a first integrator corresponding to a first pixel column at which the defect pixel is located is smaller than a second integration number of pixel data of a second integrator corresponding to a second pixel column at which the defect pixel is not located. ### Claim 13 (depends on 12) The image sensor as claimed in claim 12, further comprising a memory configured to record a pixel position of at least one defect pixel of the pixel array. ### Claim 14 (depends on 13) The image sensor as claimed in claim 13, wherein the pixel position of the at least one defect pixel is recorded before shipment or recorded in a test mode during operation. ### Claim 15 (depends on 12) The image sensor as claimed in claim 12, wherein the multiple integrators are respectively configured to integrate pixel data of a same position of the scene in adjacent image frames. ### Claim 16 (depends on 12) The image sensor as claimed in claim 12, further comprising a processor configured to ratio-amplify the pixel data integrated by the first integrator according to a ratio equal to the second integration number divided by the first integration number.