Patent ID: 7532654
Filing Date: 2009-05-12
Classification: H01S

Abstract:
1. A laser diode comprising: a substrate; and a laminated structure including a first conductive semiconductor layer, an active layer having a light emitting region, and a second conductive semiconductor layer having a projecting part on the surface thereof, on the substrate, wherein: a return light inhibition part is provided on a main-emitting-side end face, and effects of return light in the vicinity of lateral boundaries of the light emitting region are inhibited by the return light inhibition part, a reflector film is included in the main-emitting-side end face side as the return light inhibition part, and in the reflector film, laser light reflectance to the vicinity of a lateral center of the light emitting region is higher than laser light reflectance to the vicinity of lateral boundaries of the light emitting region, wherein the reflector film includes: a first coating layer covering a whole area of the main-emitting-side end face; and a second coating layer on said first coating layer and covers the vicinity of the lateral center of the light emitting region, the width of the second coating layer being 20% to 80% of the width of the light emitting region in the vicinity of the center between the main-emitting-side end face and an opposite-side end face, wherein a difference between the laser light reflectance to the vicinity of the lateral center and the laser light reflectance to the vicinity of the lateral boundaries of the light emitting region is 5% to 30%.