SEMICONDUCTOR LASER MODULE, LASER UNIT, AND RAMAN AMPLIFIER

摘要

The present invention provides a semiconductor laser module emitting a laser beam from a resonance section having a semiconductor laser device and a diffraction grating therein, and the semiconductor laser device is set in the multimode oscillation state, and by controlling a reflectivity spectrum form or a reflectivity of the diffraction grating, a laser beam spectrum emitted from the resonance section is arranged so that a plurality of longitudinal modes may be included within -3 dB from an optical amplitude of a main peak as a reference in a prespecified wavelength band widths including the main peak.