| 摘要 |
PURPOSE:To eliminate the optical path difference of the transmission line between the signal light and the reference light in an optical transmission using the optical interference, by transmitting both the signal light and the reference light received the modulation after superposing them on the same transmission line. CONSTITUTION:The output beam of a semiconductor laser 1 is divided into two beams by a half mirror 2. One of thses two beams receives the modulation of phase through an optical modulator 4 and in accordance with the electric signal applied to a terminal 3 and is reflected by a mirror 5 to be applied to a half mirror 6. The other part of the divided beams is reflected by a mirror 7 and synthesized with the beam received the modulation of phase at the mirror 6 and transmitted to the receiving side through an optical transmission line. At the receiver side, the beat component of the light received the modulation of phase and the reference light respectively is extracted by a photodetector 9 like an avalanche photodiode, etc. and then amplified by an amplifier 10 to be extracted to a terminal 11 as a received signal. |
