Patent ID: 6433823
Filing Date: 2002-08-13
Classification: H04N

Abstract:
A solid state image sensing device comprising:a plurality of photoelectric conversion elements, each of which possesses its own gamma characteristic and receives an optical signal and outputs an electrical signal corresponding to an amount of light received; a logarithmic conversion unit for performing a logarithmic conversion on the electrical signal generated in the photoelectric conversion element as well as the output from the photoelectric conversion element; a gamma correction circuit for correcting discrepancies in the gamma characteristics of each output from the photoelectric conversion element once this output has undergone the logarithmic conversion by the logarithmic conversion unit, wherein the gamma correction circuit multiplies defined values for individual pixels and thereby performs gamma correction on an output value from a photoelectric conversion element once this output value has undergone a logarithmic conversion in a logarithmic conversion unit; and a memory for storing data output by each photoelectric conversion element and calculates defined values based on the thus stored data, wherein the memory stores a first output value when a beam of a first luminance is projected and stores a second output value when a beam of a second luminance different than the first is projected, and calculates the defined values based on the following expression: a/|&agr;mâˆ’&bgr;m|wherein:a=a selected constant; &agr;m=the first output value; and &bgr;m=the second output value.