Image pickup apparatus including image pickup devices having sensitivity in infrared region

• US 20080203305A1
• Filed: 02/28/2008
• Published: 08/28/2008
• Est. Priority Date: 02/28/2007
• Status: Active Grant

• Current Assignee: Semiconductor Components Industries LLC (ON Semiconductor Corporation)
• Original Assignee: Sanyo Electric Company Limited (Panasonic Holdings Corporation)
• Inventors: Suzuki, Kazuhiro
• Granted Patent: US 7,705,308 B2
• Time in Patent Office: Days
• US Class Current: 250/338.1
• CPC Class Codes: H01L 27/14621 Colour filter arrangements
• CPC Class Codes: H01L 27/14649 Infrared imagers
• CPC Class Codes: H04N 2209/047 using multispectral pick-up elements
• CPC Class Codes: H04N 23/11 for generating image signals from visible and infrared light wavelengths
• CPC Class Codes: H04N 25/131 including elements passing infrared wavelengths
• CPC Class Codes: H04N 25/135 based on four or more different wavelength filter elements
• CPC Class Codes: H04N 5/33 Transforming infrared radiation cameras or camera modules for generating image signals from infrared radiation H04N23/20; circuitry of SSIS for transforming infrared radiation into image signals H04N25/20

Abstract

A plurality of first pixels receive both visible light and infrared light. A plurality of second pixels receive infrared light. A ratio calculation unit calculates the ratio of an output signal of another first pixel different from saturated first pixel and an output signal of a second pixel corresponding to the another first pixel. A signal estimation unit multiplies the output signal of a second pixel corresponding to the saturated first pixel, by the ratio calculated by the ratio calculation unit. A subtractor subtracts the output of a second pixel corresponding to the saturated first pixel, from a signal estimated as an output signal of the saturated first pixel.

Claims

1. An image pickup apparatus, comprising:

a plurality of first pixels which receive both visible light and infrared light;

a plurality of second pixels which receive infrared light corresponding respectively to the plurality of first pixels; and

a processing unit which obtains a component of visible light incident on a first pixel saturated with the light, by using a relation between an output signal of another first pixel different from the saturated first pixel among the plurality of first pixels and an output signal of a second pixel corresponding to said another first pixel.

2. An image pickup apparatus according to claim 1, said processing unit including:

a ratio calculation unit which calculates a ratio of the output signal of another first pixel and the output signal of a second pixel corresponding to said another first pixel;

a signal estimation unit which multiplies the output signal of a second pixel corresponding to the saturated first pixel, by the ratio calculated by the ratio calculation unit; and

a subtractor which subtracts the output of a second pixel corresponding to the saturated first pixel, from a signal obtained from a resulting multiplication in the signal estimation unit.

3. An image pickup apparatus according to claim 2, said processing unit further including a saturation decision unit which determines whether the output signal of the first pixel is saturated or not, and

wherein when an estimated signal is less than a saturation value of the first pixel after estimation of the output signal of the first pixel which has been determined to be saturated by the saturation decision unit, said signal estimation unit outputs a signal having a value greater than or equal to the saturation value.

4. An image pickup apparatus according to claim 2, wherein said ratio calculation unit calculates the ratio of the output signal of another first pixel which is estimated to have at least one of an object and a light source common to the saturated first pixel and the output signal of a second pixel corresponding to said another first pixel.

5. An image pickup apparatus according to claim 1, said processing unit including:

a calculation unit which calculates a difference between the output signal of another first pixel and the output signal of a second pixel corresponding to said another first pixel;

a signal estimation unit which adds the difference calculated by the calculation unit, to the output signal of a second pixel corresponding to the saturated first pixel; and

a subtractor which subtracts the output of a second pixel corresponding to the saturated first pixel, from a signal obtained from a resulting addition in said signal estimation unit.

6. An image pickup apparatus according to claim 1, wherein the first pixels and the second pixels are formed on the same image pickup device.

7. An image pickup apparatus according to claim 2, wherein the first pixels and the second pixels are formed on the same image pickup device.

8. An image pickup apparatus according to claim 3, wherein the first pixels and the second pixels are formed on the same image pickup device.

9. An image pickup apparatus according to claim 4, wherein the first pixels and the second pixels are formed on the same image pickup device.

10. An image pickup apparatus according to claim 1, wherein said another first pixel is an unsaturated pixel.

11. An image pickup apparatus according to claim 2, wherein said another first pixel is an unsaturated pixel.