| 摘要 |
PURPOSE:To realize electronically easily the shutter speed extending from an ultra-high speed to a comparatively low speed by providing a gate circuit between a photoelectric conversion section and a storage transfer section of an image pickup element, adjusting the opening time of the gate circuit to control the exposure time substantially. CONSTITUTION:Light emitted from an object is made incident to the photoelectric conversion section of a solid-state image pickup element 13 via a lens 11 and aperture blades 12. The photoelectric conversion section generates a current in response to the light and this current goes to an output video signal of the element 13 for only the gate pulse's width inputted via a buffer circuit 20 from a gate pulse generating circuit 18. This video signal is outputted from an output terminal 23 after the amplification, and required conversion and compensation are done at a video processing circuit 14. This video signal is branched, the photometric area is limited at a photometric area selection circuit 15, rectified at a rectifier circuit 16, compared with a reference voltage at a comparison amplifier circuit 17 and a positive voltage is outputted when the video output is larger than a suitable value and a negative voltage is outputted when smaller. A gate pulse generating circuit 18 changes the gate pulse width in response to the output of the circuit 17. |
