Image sensor optimization

Patent metadata

Field	Value
Publication number	US-9398279-B2
Application number	US-201013637900-A
Country	US
Kind code	B2
Filing date	Mar 29, 2010
Priority date	Mar 29, 2010
Publication date	Jul 19, 2016
Grant date	Jul 19, 2016

Abstract

An apparatus including: a plurality of photodetectors for converting the light to which they are exposed to into signals for image generation, wherein the photodetectors use locally optimized saturation signal. The apparatus is, for example, an image sensor or an electronic communication device.

First claim

We claim:

1. An apparatus comprising:
a plurality of photodetectors configured to convert the light to which they are exposed to into signals for image generation, wherein the photodetectors form an image plane divided into two or more areas, and wherein
the photodetectors are configured to use locally optimized saturation signal, wherein the locally optimized saturation signal is such that saturation signal of photodetectors in different areas is independent from saturation signal in other areas, and wherein the apparatus comprises a processor configured
to determine current image capturing condition, and
to control the photodetectors to change between locally optimized saturation signal and globally optimized saturation signal based on determined image capturing condition, wherein the globally optimized saturation signal is such that the photodetectors use the same saturation signal.

2. The apparatus of claim 1 , wherein the two or more areas each comprise one pixel.

3. The apparatus of claim 1 , wherein the photodetectors form an image plane having a center part and corner areas, and wherein the locally optimized saturation signal is such that photodetectors in the center part use higher saturation signal than photodetectors in the corners areas.

4. The apparatus of claim 1 , wherein the photodetectors are configured to use locally optimized saturation signal in bright light conditions and globally optimized saturation signal in low light conditions.

5. The apparatus of claim 1 , further comprising:
a processor configured to control the photodetectors to use locally optimized saturation signal.

6. The apparatus of claim 1 , wherein the image capturing condition is illumination condition or exposure condition.

7. The apparatus of claim 1 , wherein the processor is configured
to control the photodetectors to gradually change between locally optimized saturation signal and globally optimized saturation signal.

8. The apparatus of claim 1 , wherein the apparatus is an electronic communication device.

9. A method comprising:
exposing photodetectors of an image sensor to light for obtaining image data, wherein the photodetectors form an image plane divided into two or more areas,
using locally optimized saturation signal in the photodetectors, wherein the locally optimized saturation signal is such that saturation signal of photodetectors in different areas is independent from saturation signal in other areas,
determining current image capturing condition, and
controlling the photodetectors to change between locally optimized saturation signal and globally optimized saturation signal based on determined image capturing condition, wherein the globally optimized saturation signal is such that the photodetectors use the same saturation signal.

10. The method of claim 9 , wherein the photodetectors form an image plane having a center part and corner areas, and wherein the locally optimized saturation signal is such that photodetectors in the center part use higher saturation signal than photodetectors in the corners areas.

11. The method of claim 9 , further comprising using locally optimized saturation signal in the photodetectors in bright light conditions and using globally optimized saturation signal in the photodetectors in low light conditions.

12. An apparatus comprising:
at least one processor; and
at least one memory including computer program code;
the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus to perform:
controlling an image sensor comprising photodetectors, wherein the photodetectors form an image plane divided into two or more areas,
determining current image capturing condition, and
controlling the photodetectors of the image sensor to change between locally optimized saturation signal and globally optimized saturation signal based on determined image capturing condition, wherein the locally optimized saturation signal is such that saturation signal of photodetectors in different areas is independent from saturation signal in other areas, and wherein the globally optimized saturation signal is such that the photodetectors use the same saturation signal.

13. The apparatus of claim 12 , wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the apparatus to perform:
controlling the photodetectors to gradually change between locally optimized saturation signal and globally optimized saturation signal.

14. A method comprising:
controlling an image sensor comprising photodetectors, wherein the photodetectors form an image plane divided into two or more areas,
determining current image capturing condition, and
controlling the photodetectors of the image sensor to change between locally optimized saturation signal and globally optimized saturation signal based on determined image capturing condition, wherein the locally optimized saturation signal is such that saturation signal of photodetectors in different areas is independent from saturation signal in other areas, and wherein the globally optimized saturation signal is such that the photodetectors use the same saturation signal.

15. The method of claim 14 , further comprising
controlling the photodetectors to gradually change between locally optimized saturation signal and globally optimized saturation signal.

Assignees

• Alakarhu Juha
• Salmelin Eero
• Nokia Technologies Oy

Inventors

• Alakarhu Juha
• Salmelin Eero

Classifications

• H04N25/57

  Control of the dynamic range · CPC title

• H04N25/61

  the noise originating only from the lens unit, e.g. flare, shading, vignetting or "cos4" · CPC title

• H10F39/8023 Primary

  Disposition of the elements in pixels, e.g. smaller elements in the centre of the imager compared to larger elements at the periphery · CPC title

• H04N5/355

  Electricity · mapped topic

• H04N9/643 Primary

  Hue control means, e.g. flesh tone control · CPC title