| 摘要 |
PURPOSE:To attain unit forming of a radiating wave synthesis section and a photodetection branching section by utilizing both sides of an interference thin film filter provided on an optical transmission line formed as a closed loop so as to conduct the wave synthesis operation and the branching operation together. CONSTITUTION:Irradiating light sources L11, L12, L13 of a station 1 radiate respectively prescribed wavelengths lambda1, lambda2, lambda3 at first and a signal is added to the light of the wavelengths. The light of the wavelengths lambda1, lambda2, lambda3 as an optical signal touch on the surface of corresponding interference thin film filters F1, F2, F3, propagates counter clockwise and the light of the wavelengths lambda1, lambda2, lambda3 is synthesized and subject to multiplex. The synthesized wavelength multiplex light is made incident to a station 2, and when the light is inputted to the circuitry of the station 2, the light of the wavelength lambda3 is extracted at a photodetector R32 at the interference thin film filter F3, the light of the wavelength lambda2 is extracted by a photodetector R22 at the interference thin film filter F2, and the light of the wavelength lambda1 is extracted by the photodetector R12 at the interference thin film filter F1. The light is branched by using the back side of the interference thin film filters F1, F2, F3 in this way and then transmitted to a signal processing circuit of each optical signal, where the signal is processed. |
