Patent ID: 7948533

Claim:
A solid-state image sensor comprising: a pixel array unit including a plurality of pixels arranged in an array; column signal lines adapted to transmit pixel signals output from pixels in respective columns; a noise adding unit adapted to add two-dimensional spatially random noise to the pixel signals transmitted via the column signal lines; and an analog-to-digital converter adapted to convert a signal level and a reference level for each pixel signal including the noise added thereto by the noise adding unit, a pixel resetting unit adapted to reset the pixels; and an offset eliminating unit adapted to eliminate an offset of the analog-to-digital converter, wherein the noise adding unit injects a part of reset noise occurring when the resetting operation is performed by the pixel resetting unit, as noise which remains without being eliminated by the offset elimination operation performed by the offset eliminating unit; and wherein the noise adding unit controls the pixel resetting unit and the offset eliminating unit such that after the offset eliminating unit starts the operation of eliminating the offset of the comparator, the pixel is reset by the pixel resetting unit before the offset elimination operation is released, and the offset elimination operation performed by the offset eliminating unit is released before reset noise occurring in the pixel resetting operation performed by the pixel resetting unit completely settles.