| 摘要 |
PURPOSE:To make it possible to send a transmitted signal without any instantaneous break even if a circuit runs into trouble, by making a connections between a transmitting terminal and receiving terminal for light signals in parallel by light transmission lines. CONSTITUTION:An electric signal to be transmitted is converted by electrophoto converter 1 into a light signal, which is branched by the light branching device to two. One light signal output branched is amplified by light repeaters 3 and 4, phase- adjusted by light delay circuit 5, and further level-adjusted by light attenuator 6 before being sent to photocoupler 11. On the other hand, the other light signal output branched by branching device 2 is amplified by repeaters 7-9 successively and sent to coupler 11 via light attenuator 10. Then, a light signal synthesized by coupler 11 is sent to photoelectric converter 12 and converted into an electric signal. Therefore, even one circuit gets out of order, the light signal which is but a half is transmitted via the other transmission circuit, so that an instantaneous break of the light signal due to the transmission circuit can be prevented completely. |
