| 摘要 |
PURPOSE:To obtain an optical demultiplexer which is easily manufactured and has small light loss by forming a linear diffraction grating directly on curved surface of a dielectric which has the curved surface as its one flank. CONSTITUTION:The transparent dielectric 1 has curvature laterally on one surface, plane surfaces as three other flanks, and parallel top and reverse surfaces. In this case, numbers of linear grating grooves parallel to the center axis of curvature are formed on the surface with said curvature and the curved- surface linear diffraction grating 2 is formed of them. A terminal of an input optical fiber 3 and starting terminals of plural output optical fibers 4-8 are joined onto the flank facing the curved surface diffraction grating 2. Light beams having plural different wavelengths are made incident on the curved surface linear diffraction grating 2 through the dielectric 1, wavelength-dispersion there and reflected at different angles corresponding to the respective wavelengths while converged, and then projected from the output optical fibers 4-8. |
