| 摘要 |
PURPOSE:To provide an optical circuit and an optical transmitting system capable of decreasing the number of parts, and able to be simply composed and assembled. CONSTITUTION:In the forward direction, a light beam from an input fiber 1 is polarized and separated by means of a birefringent crystal 2, the separated beams are rotated by 22.5 deg. counterclockwise by means of a Faraday rotator 5, subjected to wavelength dispersion by a diffraction grating 6 and thereafter, again rotated by 22.5 deg. counterclockwise by means of the Faraday rotator 5 and further rotated by 45 deg. counterclockwise by means of a half wavelength plate 3. Therefore, the respective polarized beams are synthesized by means of the birefringent crystal 2 and only a light beam with a desired wavelength is coupled to an output fiber 8. In the backward direction, since a light beam from the output fiber 8 acts so as not to be coupled to the input fiber 1, the direction of light propagation is prescribed to one direction. |
