OPTICAL DEMULTIPLEXER, DIFFRACTION GRATING AND WAVE-MULTIPLEXED LIGHT TRANSMISSION MODULE

摘要

PROBLEM TO BE SOLVED: To achieve a chirp type diffraction grating in which aberration caused by the variation in wavelength is reduced and to achieve an optical demultiplexer having low cross talk. SOLUTION: The incident position and the emitting position at a designed wavelength are decided so as to reduce the aberration caused in the chirp type diffraction grating 14. Particularly, in order to reduce the aberration (coma-aberration) proportionate to the third power of the distance from the center of the chirp type diffraction grating 14, the incident angle is made larger than the emitting angle and the emitting distance is made larger than the incident distance. COPYRIGHT: (C)2006,JPO&NCIPI