Vertical cavity surface emitting laser

摘要

The present invention provides a Vertical Cavity Surface Emitting Laser including: a first multilayer film reflector; an active layer having a light emission region; a second multilayer film reflector; and a reflectance adjustment layer in this order on a substrate side. The first multilayer film reflector and the second multilayer film reflector have a laminated structure in which reflectance of oscillation wavelength λx is almost constant without depending on temperature change. The active layer is made of a material with which a maximum gain is obtained at temperature higher than ambient temperature. The reflectance adjustment layer has a laminated structure in which difference &Dgr;R(=Rx−Ry) between reflectance Rx of a region opposed to a central region of the light emission region and reflectance Ry of a region opposed to an outer edge region of the light emission region is increased associated with temperature increase from ambient temperature to high temperature.