| 摘要 |
PURPOSE:To constitute an optical demultiplexer in an extremely simple shape by using a plane curved diffraction grating. CONSTITUTION:A dielectric 1 where the plane curved diffraction grating have curved grating grooves formed in one surface of a plane reflecting plate so as to have light converging effect, and is provided with a metallic film 15 so as to make the plane curved diffraction grating reflective. End parts of optical fibers 3, 4, 5, 6, 7, and 8 are inserted into recessed parts 9, 10, 11, 12, 13, and 14 formed in one end surface of a transparent prismatic dielectric 2, and the prismatic dielectric 2 and optical fibers 3, 4, 5, 6, 7, and 8 are united together by using a material whose refractive index is nearly equal to that of said optical fibers. Light having five different wavelengths is made incident from the input optical fiber 3 and passed through said dielectric 2, and this light is wavelength- dispered by a dielectric where a plane curved diffraction grating is formed, reflected by the metallic film 9 at different angles corresponding to the wavelengths, and converged by the plane curved diffraction grating 1, so that light beams having the mutually different wavelengths are photodetected by the optical fibers 4, 5, and 6. |
