| 摘要 |
PURPOSE:To erase a picture in a period in which a flicker phenomenon is occurring by activating a picture erasing circuit that cuts off and controls video output signals of a video amplifier circuit only in a period in which deflection position on a image pickup tube is shifted by a rotary deflection controlling circuit. CONSTITUTION:An image pickup tube 2 is rotatively deflected by a deflecting circuit 1 and a rotary deflection controlling circuit 3, and output signals are added to a video signal amplifier circuit 4 and amplified. When an output of the circuit 3 is in fixed state and a rotation is stopped, a picture erasing circuit 5 does not work and signals of the image pickup tube 2 are amplified and outputted to a video output terminal 6. During rotary operation in which the circuit 3 operates, the circuit 5 operates and signals in which video signal components are cut off are outputted to the terminal 6. Consequently, a flicker generated when deflection position is moved by rotary deflection does not appear in the terminal 6, and a picture free from flicker can be observed. |
