| 摘要 |
PURPOSE:To attain cordless configuration by separating the titled device into a block converting a field pulse corresponding respectively to an odd/even number field into an optical signal and a block of a shutter including a photodetection section and a drive section and utilizing light. CONSTITUTION:A field pulse corresponding to an odd/even number field of a video signal 1 is generated by a synchronizing separator 2 and converted into an optical signal by a modulator 5 and a light emitting device 6 via a field discriminator 3 and an FF 4. The light receiving device 7 receives an optical signal of the light emitting device 6 and converts in into an electric signal, which is demodulated by a high frequency amplifier 8, a band pass filter 9 and a demodulator 10 to obtain a pulse C (pulse C'). A pulse I from a pulse generator 14 is deviated by one field to a pulse E from the pulse generator 11. Amplifiers 13a, 13b are operated in the period of oscillated pulse G, K corresponding to the period of high level pulses E, J and shutter operation is applied alternately synchronously with a video field. |
