Electronic endoscope apparatus

Claim 1

An image-pickup device having a plurality of color filters arranged in units of pixels; light shielding means for intercepting illumination light so that pixel signals for a predetermined period of time are not accumulated on said image-pickup device; switching means for switching driving control for both a pixel mix reading system, which mixes pixels accumulated on said image-pickup device between upper and lower horizontal lines to output from said image-pickup device, and an all-pixel reading system, which reads out signals of all pixels accumulated on said image-pickup device by one exposure through the use of a light shielding period set by said light shielding means; an image-pickup device driving circuit for controlling so as to read out, concerning all pixel signals accumulated on said image-pickup device by one exposure, image signals on either odd or even horizontal line first, and next to read out image signals on the remaining horizontal line; a memory for storing, at the execution of said all-pixel reading system, image signals on said odd horizontal line obtained from said image-pickup device and image signals on said even horizontal line; a phase adjustment memory for adjusting a phase, at the execution of said all-pixel reading system, between image signals on a predetermined horizontal line previously stored in said memory and image signals on another horizontal line; a mixing circuit for forming a still image signal by mixing pixel signals of said odd horizontal line and said even horizontal line during the same exposure which have been read out from said memory for storing image signals and said phase adjustment memory; and an image switching circuit for directly inputting a moving image signal of the pixel mix reading system outputted from said image-pickup device to switch either said moving image signal or a still image signal outputted from said mixing circuit on the basis of the operation of a freeze switch.