| 摘要 |
PURPOSE:To enable the simultaneous communication in two ways by means of a single luminous element by leading out the transmitting optical signal through branch-off of the received optical signal. CONSTITUTION:Communicating apparatus 6 consisting of optical transmission circuit 2 incorporating the luminous element and optical reception circuit 3 is installed, along with communication apparatus 7 comprising circuit 3 and optical modulator circuit 5 plus the return optical transmission line between apparatus 6 and 7. Thus the modulation is given so that the nearly constant average electric power may be ensured for the going optical signal from apparatus 6 to 7. And part of the reception power of the going optical signal is branched off through optical modulator circuit 5 to be piled, thus using the optical signal which underwent the intensity modulation for the coming-back optical signal from apparatus 7 to 6. The avalanche photo diode is used for the photo detector in circuit 3 of apparatus 6, and the photo diode is used for circuit 3 of apparatus 7 respectively. |
