Optical communication module, manufacturing method thereof and wavelength selective filter

摘要

The incident angle of the beam with regard to an etalon is arranged finely tunable by either rotating the etalon provided with a plane of incidence inclined with regard to the rotational axis thereof in the vicinity of the optical axis or rotating a lens whose edge surface is obliquely ground around the optical axis, which allows the incident angle of the laser beam with regard to the etalon to be adjusted and fixed with high precision.