JPS6424488A - Semiconductor laser device - Google Patents

Abstract

PURPOSE:To reflect light rays regularly without irregular reflection in such a direction as not to cause the interference of the reflected light rays with projected light beam by a method wherein a return light incident region of a sub-mount laser projecting end face is provided as a cleavage face which forms a oblique angle with a primary face parallel to the direction in which the laser beam is projected. CONSTITUTION:A semiconductor laser chip 31 is die-bonded to a plate-like sub-mount 81 and a required voltage is applied onto the chip 31, a laser beam MB is projected from an active layer 3a in a direction parallel to the primary face S. A side end face T of the sub-mount 81 laser projecting beam face is composed of a wall face Ta of a dicing angle groove and a cleavage face Tb, where a return light BB, which travels from an outer optical system device toward a light source of the semiconductor laser chip 31, is incident on a return light incident region Tb' surrounded by a broken line in a cleavage face Tb and regularly reflected there in such a direction as not to interfere with a main beam. In addition, provided that a submount is formed of a single crystal, a primary face S intersects the cleavage face Tb at an angle theta of about 109.5 deg., where the primary face is 111 face.