Patent ID: 7190399

Claim:
A solid-state image pickup apparatus comprising: a plurality of pixels each with a photoelectric conversion element, a logarithmic converter including a logarithmic-converting transistor for converting an output of the photoelectric conversion element into an electric signal proportional to a logarithmic value of an amount of light incident on the photoelectric conversion element, and an integration circuit for accumulating an output from the logarithmic converter; a voltage controller for controlling a voltage to be applied to the logarithmic-converting transistor; and an output circuit for receiving signals from the pixels and outputting signals; wherein the voltage controller is configured such that a first voltage for image pickup is applied to the logarithmic-converting transistor while a first signal outputted through the logarithmic converter from the photoelectric conversion element is accumulated at the integration circuit, a second voltage for resetting the logarithmic-converting transistor is applied to the logarithmic-converting transistor while a second signal outputted through the logarithmic converter from the photoelectric conversion element is accumulated at the integration circuit, and the second voltage is set at a value at which an absolute value of difference between the first voltage and the second voltage is lower than a value at which a normal image pickup state is achievable, thereby realizing a moving object extraction image pickup state in which an image pickup signal is generated for displaying at least a part of a moving object existing in an image picked-up region at a density different from that of a static background part existing in the image picked-up region; and wherein the output circuit outputs the signals each corresponding to difference between the first signal and the second signal.