Global shutter with dual storage

• US 9,100,605 B2
• Filed: 02/07/2012
• Issued: 08/04/2015
• Est. Priority Date: 02/09/2011
• Status: Active Grant

• Current Assignee: Stmicroelectronics (Research & Development) Limited (STMicroelectronics NV)
• Original Assignee: Stmicroelectronics (Research & Development) Limited (STMicroelectronics NV)
• Inventors: Raynor, Jeffrey M.
• Primary Examiner(s): Luu, Thanh
• Application Number:
  US13/984,305
• Publication Number:
  US 20140008520A1
• Time in Patent Office: 1,274 Days
• Field of Search: 250/208.1, 348/308
• US Class Current: 1/1
• CPC Class Codes: H01L 27/14612 involving a transistor
• CPC Class Codes: H01L 27/14643 Photodiode arrays; MOS imagers
• CPC Class Codes: H01L 27/14683 Processes or apparatus peculiar to the manufacture or treatment of these devices or parts thereof not peculiar thereto H01L21/00
• CPC Class Codes: H01L 27/14689 MOS based technologies
• CPC Class Codes: H04N 25/00 Circuitry of solid-state image sensors [SSIS]; Control thereof
• CPC Class Codes: H04N 25/533 by using differing integration times for different sensor regions
• CPC Class Codes: H04N 25/616 involving a correlated sampling function, e.g. correlated double sampling [CDS] or triple sampling
• CPC Class Codes: H04N 25/75 Circuitry for providing, modifying or processing image signals from the pixel array
• CPC Class Codes: H04N 25/77 Pixel circuitry, e.g. memories, A/D converters, pixel amplifiers, shared circuits or shared components
• CPC Class Codes: H04N 25/771 comprising storage means other than floating diffusion
• CPC Class Codes: H04N 25/78 Readout circuits for addressed sensors, e.g. output amplifiers or A/D converters

Abstract

A sensor includes an array of pixels, and a global shutter configured to expose the array of pixels. Each pixel includes storage elements configured to independently store successive frames within a predetermined time period. Each storage element is configured to be independently read out.

Claims

1. A sensor comprising:

an array of pixels, with each pixel comprising

a photodiode,

a floating diffusion capacitor coupled to a floating diffusion node,

a transfer gate transistor coupled between said photodiode and said floating diffusion capacitor and configured to transfer a charge to said photodiode during pixel reset and during pixel readout from said photodiode to the floating diffusion node, and

a plurality of storage elements coupled to the floating diffusion node and configured to independently store a plurality of successive frames within a predetermined time period, and with each storage element being configured to be independently read out; and

a global shutter configured to expose the array of pixels.

2. The sensor of claim 1, wherein the storage elements are configured to be read out simultaneously.

3. The sensor of claim 1, further comprising a single bit line configured to read out the storage elements.

4. The sensor of claim 1, further comprising a plurality of bit lines, each storage element being configured to be read out via a different bit line.

5. The sensor of claim 4, wherein the plurality of bit lines comprises two bit lines, and wherein the plurality of storage elements comprises two storage elements.

6. The sensor of claim 1, wherein each storage element comprises at least one transistor.

7. The sensor of claim 1, wherein each storage elements comprises at least one capacitor.

8. The sensor of claim 1, further comprising processing circuitry coupled to the plurality of storage elements and configured to process a plurality of successive frames so as to determine ambient light conditions.

9. The sensor of claim 1, further comprising processing circuitry coupled to the plurality of storage elements and configured to process a plurality of successive frames so as to determine movement of an object from one frame to a successive frame.

10. The sensor of claim 9, wherein the processing circuitry generates a control signal based on movement of the object.

11. An electronic device comprising:

a sensor comprising

an array of pixels, each pixel comprising

a photodiode,

a floating diffusion capacitor coupled to a floating diffusion node,

a transfer gate transistor coupled between said photodiode and said floating diffusion capacitor and configured to transfer a charge to said photodiode during pixel reset and during pixel readout from said photodiode to the floating diffusion node, and

a plurality of storage elements configured to independently store a plurality of successive frames, each storage element being configured to be independently read out, and

a global shutter configured to expose the array of pixels.

12. The electronic device of claim 11, wherein the electronic device is configured to define a machine vision device.

13. The electronic device of claim 11, wherein the electronic device is configured to define a computer.

14. The electronic device of claim 11, wherein the electronic device is configured to define a phone.

15. The electronic device of claim 11, wherein the electronic device is configured to define a camera.

16. The electronic device of claim 11, wherein the electronic device is configured to define a touch screen.

17. The electronic device of claim 11, wherein the electronic device is configured to define a remote controller.

18. An image capture method comprising:

simultaneously exposing each pixel in an array of pixels, with each pixel comprising a photodiode, a floating diffusion capacitor coupled to a floating diffusion node, a transfer gate transistor coupled between the photodiode and the floating diffusion capacitor and configured to transfer a charge to the photodiode during pixel reset and during pixel readout from the photodiode to the floating diffusion node, and a plurality of storage elements coupled to the floating diffusion node;

independently storing within the plurality of storage elements of each pixel a plurality of successive frames within a predetermined time period such that the plurality of successive frames are stored simultaneously in the plurality of storage elements within each pixel; and

independently reading out each of the successive frames from the plurality of storage elements in each pixel.

19. The image capture method of claim 18, wherein the simultaneously stored successive frames are read out simultaneously.

20. The image capture method of claim 18, wherein the plurality of successive frames are read out via a single bit line.

21. The image capture method of claim 18, wherein each of the simultaneously stored plurality of successive frames are read out via dedicated bit lines.

22. The image capture method of claim 21, wherein two successive frames are stored within each pixel.

23. The image capture method of claim 18, wherein the plurality of successive frames are processed to determine ambient light conditions.

24. The image capture method of claim 18, wherein the plurality of successive frames are processed to determine movement of an object from one frame to a successive frame.

25. The image capture method of claim 24, wherein the movement of the object is used to generate a control signal for the device.

26. A method of making a sensor comprising:

forming an array of pixels, with each pixel of the array comprising

a photodiode,

a floating diffusion capacitor coupled to a floating diffusion node,

a transfer gate transistor coupled between said photodiode and said floating diffusion capacitor and configured to transfer a charge to said photodiode during pixel reset and during pixel readout from said photodiode to the floating diffusion node, and

a plurality of storage elements coupled to the floating diffusion node and configured to independently store a plurality of successive frames, with each storage element being configured to be independently read out; and

configuring a global shutter to expose the array of pixels.

27. The method of claim 26, wherein the storage elements are configured to be read out simultaneously.

28. The method of claim 26, further comprising configuring at least one bit line to read out the storage elements.

29. The method of claim 26, further comprising configuring processing circuitry coupled to the plurality of storage elements to process a plurality of successive frames to determine ambient light conditions.

30. The method of claim 26, further comprising configuring processing circuitry coupled to the plurality of storage elements to determine movement of an object from one frame to another frame.