SEMICONDUCTOR LASER APPARATUS

摘要

PROBLEM TO BE SOLVED: To provide a semiconductor laser apparatus which can precisely control light intensity Pa of main light 6 with light intensity Pb of monitoring light 8 and highly precisely output light of high light power. SOLUTION: In the semiconductor laser device 20, light caused in an active layer 2 is emitted from one end face 3a as main light 6 and as monitoring light 8 monitoring an output characteristic of main light from the other end face 3b, a main light-side reflecting film 9 is formed on an end face from which main light is emitted, and a monitoring light side reflecting film 21 whose reflectance is higher than the main light-side reflecting film 9 is formed on an end face from which monitoring light is emitted. A reflectance Rb of light in the monitoring light-side reflecting film 21 depends on a wavelength of incident light and changes. A wavelengthλMof incident light with which the reflectance Rb of light becomes the largest is set to be shorter than the shortest wavelengthλSin use in a wavelength range (λStoλL) in use which is previously decided in main light. COPYRIGHT: (C)2004,JPO&NCIPI