| 摘要 |
PURPOSE:To obtain a semiconductor laser device having excellent characteristics of reflectivity of approximately 60% in the rear end surface of a resonator with superior reproducibility by coating at least one of the end surfaces of the resonator in a semiconductor laser crystal with an Al2O3 film and an Si film. CONSTITUTION:At least one of the end surfaces 2, 3 of a resonator in a semiconductor laser crystal 1 is coated with an Al2O3 film and an Si film. The front end surface 2 of the semiconductor laser crystal 1 is coated with a coated film such as an Al2O3 coated film 3 having a film-thickness 0.5 wavelength, a rear end surface 4 is coated with a coated film such as an Al2O3 coated film 3' having a film-thickness 0.10 wavelength and the coated film 3' is coated with a coated film such as an Si coated film 5 having a 0.28 or 0.36 wavelength, or the rear end surface 4 is coated with a coated film such as an Al2O3 coated film 3' having a film-thickness 0.40 wavelength and the coated film 3' is coated with a coated film such as an Si coated film 5 having a 0.14 or 0.22 wavelength. The reflectivity of the front end surface 2 is brought to approximately 30% and the reflectivity of the rear end surface 4 to approximately 60% at that time, and an output from laser beams 6' emitted from the rear end surface is brought to 0.43 times as high as that from laser beams 6 emitted from the front end surface 2. |
