| 摘要 |
PURPOSE:To obtain a high-quality picture with less degradation of the picture quality, by detecting a smear signal, which is generated in a CCD, in the vertical blaking period and converting this signal to a DC level control signal to adjust the clamp potential to the reference black level of the picture. CONSTITUTION:The image pickup signal where a smear signal is superposed is supplied to a smear detecting circuit 21, and also a clamp circuit 24 through an amplifier 22. The smear detecting circuit 21 samples the part in the vertical blanking period of the image pickup signal to detect the smear signal, and this signal is supplied to an integrating network 23 and is converted to a DC level control signal and is supplied to the clamp circuit 24. In the clamp circuit 24, the black level signal from an image pickup element arranged in a light shielding region 19 of a CCD 15 is clamped in the DC level of the control signal which is formed on a basis of said smear signal. |
