DOUBLE-PATH MONOCHROMATER, WAVELENGTH SELECTION OPTICAL SWITCH, AND OPTICAL CHANNEL MONITOR

摘要

PROBLEM TO BE SOLVED: To provide a double-path monochromater capable of effectively increasing a spatial discrete quantity of the dispersed light of each wavelength, a wavelength selection optical switch using the same, and an optical channel monitor.;SOLUTION: The double-path monochromater includes a diffraction grating diffracting and dispersing incident light; and a reflector having a reflecting surface disposed so as to reflect the incident light diffracted by the diffraction grating three or more odd number of times and make the light re-enter the diffraction grating. In the reflector, the reflecting surface is preferably disposed so that the diffracted light re-entering the diffraction grating advances in nearly parallel with the diffracted light prior to being reflected by the reflector at a reference wavelength and re-enters the diffraction grating at a separate position from the incident light on a diffraction plane.;COPYRIGHT: (C)2011,JPO&INPIT