Semiconductor laser apparatus

摘要

A semiconductor laser apparatus includes a semiconductor laser for emitting a light beam. The semiconductor laser has, as an external cavity, a quadruple light wave mixing optical phase conjugate element for inverting a spatial phase of an incident light beam. The apparatus further includes a pair of pump light sources which are arranged such that a superimposed portion of spectra of wavelengths of three light beams including two pump light beams emitted from the pair of pump light sources and entering into the optical phase conjugate element and another light beam emitted from the semiconductor laser is narrower than the spectral width of wavelengths of each of the three light beams. This enables the laser apparatus to generate an oscillating output wavelength of extremely narrow spectral width.