Optical parts assembling method and the optical parts

摘要

An optical component assembling method, in which a first metal housing (10) holding a first optical element and a second metal housing (20) holding a second optical element are made to abut against each other on joint surfaces (10b, 20b) thereof, and irradiated with a laser beam (31) so as to be fixedly welded with each other, characterized in that one of the metal housings overhangs from the other of the metal housings, and the laser beam is radiated in an incident direction &thetas; inclined to the overhanging metal housing side so as to perform spot-welding (30) on outer circumferences of the joint surfaces where the metal housings abut against each other, whereby the decrease of light-intensity at the time of assembly is suppressed to be extremely low.