| 摘要 |
PURPOSE:To remove noises and the unevenness of sensitivity by A/D converting outputs from each picture element on an irradiation of uniform beams, obtaining a summing mean value through plural scannings and comparing the value with an output mean value from a plurality of picture elements close to each picture element. CONSTITUTION:The titled detector is driven by an image pickup element 2, to which uniform beams are projected, and a driving circuit 1. Outputs from each picture element of the image pickup element 2 are amplified by an amplifier 3 and converted by an A/D converter 4, and a summing mean value on plural scannings is memorized to a frame memory 5. A decision circuit 6 compares summing mean values at every picture element with an output mean value from a plurality of (n) picture elements close to the picture elements, and decides the picture element as a white flaw or a black flaw when there is a difference of a fixed value or more. Accordingly, random noises are removed through plural scannings, and the unevenness of illuminance of irradiating beams and the unevenness of sensitivity of the image pickup element can be removed through a comparison with the output mean value from a plurality of (n) picture elements. |
