Solid state sensor having logarithmic photovoltaic response, with pixel uniformity correction and white balance circuitry therefor

Claim 2

A solid-state image sensing apparatus comprising: a solid-state image sensing device having a plurality of pixels and a characteristic that an output voltage thereof natural-logarithmically varies in accordance with a light reception amount; storing means for storing an image sensing output signal obtained with respect to each pixel when uniform light is irradiated to the solid-state image sensing device; and calculating means for calculating a difference between an image sensing output signal obtained with respect to each pixel in actual sensing and a stored image sensing output signal with respect to a pixel corresponding thereto which signal is stored in said storing means, to form an image signal.

Claim 3

A solid-state image sensing apparatus according to claim 1, wherein said solid-state image sensing device generates each output voltage corresponding to each of three primary colors of light for sensing a color image, and said storing means stores an image sensing output voltage obtained from the solid-state image sensing device with respect to each pixel when a white light is irradiated to the solid-state image sensing device and a white balance of an image signal is realized in a calculation by said calculating means.

Claim 4

A solid-state image sensing apparatus comprising: a solid-state image sensing device having a plurality of pixels and a characteristic that an output voltage thereof natural-logarithmically varies in accordance with a light reception amount; first storing means for storing an image sensing output signal obtained from the solid-state image sensing device with respect to each pixel when a first light is irradiated to the solid-state image sensing device; second storing means for storing an image sensing output signal obtained from the solid-state image sensing device with respect to each pixel when a second uniform light of which light amount is different from that of the first uniform light is irradiated to the solid-state image sensing device; first calculating means for calculating a difference between the output signals which are stored, respectively, in the first and the second storing means with respect to each pixel; second storing means for calculating a difference between an image sensing output signal obtained with respect to each pixel in actual sensing and a stored image sensing output signal with respect to a pixel corresponding thereto which signal is stored in said second storing means; and third calculating means for calculating a ratio of the difference calculated by the first calculating means to the difference calculated by the second calculating means to form an image signal.

Claim 5

A solid-state image sensing apparatus comprising: a solid-state image sensing device having a plurality of pixels and a characteristic that an output voltage thereof natural-logarithmically varies in accordance with a light reception amount; first storing means for storing an image sensing output signal obtained from the solid-state image sensing device with respect to each pixel when a first light is irradiated to the solid-state image sensing device; second storing means for storing an image sensing output signal obtained from the solid-state image sensing device with respect to each pixel when a second uniform light of which light amount is different from that of the first uniform light is irradiated to the solid-state image sensing device; first calculating means for calculating a difference between the output signals which are stored, respectively, in the first and the second storing means with respect to each pixel; second storing means for calculating a difference between an image sensing output signal obtained with respect to each pixel in actual sensing and a stored image sensing output signal with respect to a pixel corresponding thereto which signal is stored in said second storing means; and third calculating means for calculating a ratio of the difference calculated by the first calculating means to the difference calculated by the second calculating means to form an image signal.

Claim 6

A solid-state image sensing apparatus comprising; a solid-state image sensing device having a plurality of pixels and a characteristic that an output voltage thereof natural-logarithmically varies in accordance with light reception amount; first calculating means for calculating with each pixel a difference between an image sensing output from the solid-state image sensing device when a first uniform light is irradiated to the solid-state image sensing device and an image sensing output signal from the solid-state image sensing device when a second uniform light of which light amount is different from that of the first light amount is irradiated to the solid-state image sensing device; second calculating means for calculating a difference between a sensing signal obtained with respect to each pixel in actual sensing and a stored image sensing output signal with respect to a pixel corresponding thereto obtained when the second uniform light is irradiated to the solid-state image sensing device; and third calculating means for calculating a ratio of the difference calculated by the first calculating means to the difference calculated by the second calculating means to form an image signal.

Claim 7

A solid-state image sensing apparatus comprising; a solid-state image sensing device having a plurality of pixels and a characteristic that an output voltage thereof natural-logarithmically varies in accordance with light reception amount; first calculating means for calculating with each pixel a difference between an image sensing output from the solid-state image sensing device when a first uniform light is irradiated to the solid-state image sensing device and an image sensing output signal from the solid-state image sensing device when a second uniform light of which light amount is different from that of the first light amount is irradiated to the solid-state image sensing device; second calculating means for calculating a difference between a sensing signal obtained with respect to each pixel in actual sensing and a stored image sensing output signal with respect to a pixel corresponding thereto obtained when the second uniform light is irradiated to the solid-state image sensing device; and third calculating means for calculating a ratio of the difference calculated by the first calculating means to the difference calculated by the second calculating means to form an image signal.

Claim 8

A solid-state image sensing apparatus comprising: a solid-state image sensing device having a plurality of pixels and a characteristic that an output voltage thereof natural-logarithmically varies in accordance with a light reception amount, the solid-state image sensing device is directed to generate voltage corresponding to respective three primary colors of light for sensing a color image; storing means for storing an image sensing output signal obtained from the solid-state image sensing device with respect to each pixel when white light is irradiated to the solid-state image sensing device; and calculating means for calculating a difference between an image sensing signal obtained with respect to each pixel in actual sensing and a stored image sensing output signal with respect to a pixel corresponding thereto which signal is stored in the storing means to realize a white balance of an image signal.

Claim 9

A solid-state image sensing apparatus comprising: a solid-state image sensing device having a plurality of pixels and a characteristic that an output voltage thereof natural-logarithmically varies in accordance with a light reception amount, the solid-state image sensing device is directed to generate voltage corresponding to respective three primary colors of light for sensing a color image; storing means for storing an image sensing output signal obtained from the solid-state image sensing device with respect to each pixel when white light is irradiated to the solid-state image sensing device; and calculating means for calculating a difference between an image sensing signal obtained with respect to each pixel in actual sensing and a stored image sensing output signal with respect to a pixel corresponding thereto which signal is stored in the storing means to realize a white balance of an image signal.