PURPOSE: To take out a good S/N video signal from the output signal of the CCD image pickup element.

CONSTITUTION: A band-pass filter 2 turning the frequency equivalent to a clock frequency fS at the time of taking out the output signal S1 from the solid-state image pickup element 1 to the central frequency and taking the occupancy band width of the video signal S1 as a band-pass width of the video signal and an AM detection circuit 3 AM-detecting an output signal S2 of this band- pass filter 2 are provided. The output signal S1 of the solid-state image pickup element 1 is supplied to the band-pass filter 2, and an effective signal waveform part of the output signal S2 of the band-pass filter 2 is envelope-detected in an AM detection circuit 3 so as to take out the video signal S3.