PROBLEM TO BE SOLVED: To provide a laser light irradiation device capable of shortening the time required for adjusting an optical coupling state of an emission end of an optical waveguide such as an optical fiber and an incident end of a core of an optical waveguide member.SOLUTION: A laser light irradiation device 10 includes multiple light sources 31, multiple optical waveguides 21, an optical waveguide member 22, and multiple light detecting means 32. The multiple light detecting means 32 are arranged in line in a circumferential direction of the optical waveguide member 22 around a clad 22b of the optical waveguide member 22. A relative position calculation part 33 calculates information regarding a relative position of end surfaces of the respective optical waveguides 21 and an end surface of the optical waveguide member 22 (relative position information Da) based on information regarding positions of the respective light detecting means 32 and light detection signals Sa output from the respective light detecting means 32. A drive control part 35 drives a stage 34 based on the relative position information Da such that the relative position of the end surfaces of the respective optical waveguides 21 and the end surface of the optical waveguide member 22 approaches a predetermined position.
展开▼
