External cavity-type of wavelength tunable semiconductor laser light source and method for tuning wavelength therefor

摘要

An external resonator type of wavelength tunable semiconductor laser light source comprises: a semiconductor laser provided with an anti- reflection film on one end facet thereof; a diffraction grating having a wavelength selection property, which is disposed in a side of the anti- reflection film of the semiconductor laser; and a wavelength tunable member for changing a position of the diffraction grating with respect to the semiconductor laser, to tune a wavelength of an oscillating light based on a movement of the diffraction grating, the wavelength tunable member comprises a supporting member a portion of which is fixed, a free arm of which supports the diffraction grating, and at least a part of which is an elastic body; a movement member for moving the supported diffraction grating by deforming the elastic body of the supporting member elastically; and a movement control member for controlling the amount of movement of the movement member.