| 摘要 |
PROBLEM TO BE SOLVED: To reduce optical loss caused by a carrier implanted into an optical filter and deterioration of a semiconductor caused by the carrier in the optical filter having a diffraction grating formed by a semiconductor.SOLUTION: An optical filter comprises: a waveguide formed by a semiconductor; a diffraction grating which is formed by a semiconductor and formed along the waveguide; and a plurality of heaters formed along the diffraction grating. Diffracted wavelengths of the diffraction grating at positions corresponding to the plurality of heaters are different from each other when all of the plurality of heaters are turned off. |
