| 摘要 |
PURPOSE:To make images distinct, to prevent flicker on a screen and to improve the image quality and the color reproducibility by supplying an illuminating light pulse interruptedly to control driving of a motor so that the phase difference is equal to a set phase difference. CONSTITUTION:A chopper 26 is rotated once at each one frame scanning time, and the illuminating light is not supplied into a somatic cavity when a shielding part 26b of the chopper 26 intercepts a luminous flux A of the illuminating light, and the illuminating light is supplied there only when a window 26a is in the position of the luminous flux A, and a still image is made distict by supplying the illuminating light interruptedly. A comparator 43 compares a set speed signal Ssd and a detected speed signal Ss with each other and outputs the difference signal to a motor driving circuit 44. The motor driving circuit 44 increases or reduced the power supplied to a motor 25 based on the difference signal to control the rotative speed of the shopper 26. Since the set phase difference is so determined that the time when the center part of the window part 26a passes the center part of the luminous flux A coincides with the transfer time of a picture signal to be used for odd field scanning, the middle of the supply time of the illuminating light pulse coincides with the transfer time of the picture signal.
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