SIGNAL PROCESSOR FOR ENDOSCOPE

摘要

PROBLEM TO BE SOLVED: To provide a signal processor for an endoscope preventing deterioration of an image quality by a flaw of a pixel such as a white blemish in an optical area.

SOLUTION: An output signal passing from a CCD 19 incorporating a function of varying amplification factors through a preamplifier 18 is clamped in analog in a signal output period from a dummy part with no white blemish in the CCD 19 by an analog clamp circuit 71 in an analog processing circuit 33, and similarly clamped in analog in a previous step of an A/D converter 34. A digital signal passing through the A/D converter 34 substantially eliminates the effect of the white blemish in an OB (optical black) area by a digital clamp processing using whole pixels on the OB area in the digital clamp circuit 74 to prevent the deterioration of the image quality.

COPYRIGHT: (C)2005,JPO&NCIPI