SEMICONDUCTOR LASER MODULE

PROBLEM TO BE SOLVED: To provide a semiconductor laser module having low noise and high coupling efficiency even when a reflection return beam in an optical waveguide is large and having optimum transmission quality even when a reflection return beam amount in the optical waveguide is fluctuated. SOLUTION: The semiconductor laser module is provided with a semiconductor laser 11 with a spot size conversion area, a coupled optical fiber coupled to an emission beam from the semiconductor laser 11, an angle varying device 13 varying a coupling angle between the emission end surface of the semiconductor laser 11 and the coupled optical fiber 12, a demultiplexer 14 demultiplexing the reflection return beam in the coupled optical fiber 12 and a level detector 15 detecting the level of the demultiplexed beam, and is constituted so that the coupling angle is varied by the angle varying device 13 according to the level of the beam detected by the level detector 15.