Patent attributes
A light source module includes: laser light sources; parallel light lenses that converts laser beams from the laser light sources to collimated laser beams; a demagnification optical system including that demagnifies the collimated laser beams; an optical fiber; and a condenser lens that converges and couples the laser beams demagnified by the demagnification optical system with the optical fiber; wherein an Abbe number of each of the parallel light lenses is set to a set value suppressing an output fluctuation from the optical fiber to a predetermined value or less, the set value determined based on: a transverse magnification defined by a focal length of a corresponding one of the parallel light lenses, a demagnification of the demagnification optical system, and a focal length of the condenser lens; and a corresponding one of wavelength shifts of the laser beams generated by the laser light source.
