Patent ID: 7031362
Filing Date: 2006-04-18
Classification: B82Y,H01S

Abstract:
1. A semiconductor laser device comprising: an active layer positioned between cladding layers, said active layer having a reflection side end surface configured to reflect an oscillated laser beam, and an emission side end surface configured to emit the laser beam; and a transmission film comprising a multi-layer film laminated on said emission side end surface, said transmission film having a low reflectivity of 0.5% or less within a wavelength range defined by a predetermined wavelength difference with respect to a predetermined oscillation wavelength, wherein: at least one film of said multi-layer film includes plural sub-films that collectively are optically equivalent to a single layer film, and the at least one film inclues an outer sub-film made of the same material as another film of the multilayer film which is adjacent to the outer sub-film.