| 摘要 |
PURPOSE:To set optionally an exposure time by providing an optical system forming an intermediate image to the arranging position of a shutter to prevent duplicated exposure even at a period other than blanking period. CONSTITUTION:A shutter disc 6 is arranged near an intermediate image 17 formed by the 1st optical system 16. The 2nd optical system 18 forms the intermediate image 17 again on an image pickup tube 13. A motor 12 rotates a shutter disc 6. When light is transmitted to an image pickup plane 2, an electric signal is generated. The light forming the intermediate image 17 is formed that it passes through an aperture 7 of a shutter disc 6 and a part of the light is shut off regularly in this case. That is, as the scanning is deflected, the shutter disc 6 is moved in the turning direction 8 while being synchronized so as to avoid the transmission of light to the scanned part. Thus, duplicated exposure is avoided even at a period other than the blanking in this way. |
