Patent ID: 6922425

Claim:
A semiconductor laser device comprising: a base having an anchor surface and a reference surface; and a semiconductor laser, wherein the semiconductor laser is fixed to the anchor surface of the base, and the anchor surface is inclined by a specified inclination angle with respect to the reference surface of the base, a plane of polarization of a laser beam emitted by the semiconductor laser is inclined by the specified inclination angle from a substrate surface of the semiconductor laser so as to be generally parallel to the reference surface of the base, or the plane of polarization of the laser beam is inclined by the specified inclination angle with respect to a plane vertical to the substrate surface so as to be generally vertical to the reference surface of the base, the base includes a stem body having the reference surface, and a generally L-shaped anchor portion fixed to the stem body and having the anchor surface, the anchor portion includes an X-direction portion extending generally parallel to the reference surface, and a Y-direction portion extending generally vertical to the reference surface and having a signal-detection use photodetection device mounted on its upper surface, and the X-direction portion has a reference-surface-side side face extending generally parallel to the reference surface and an opposite-side side face containing the anchor surface, the opposite-side side face being opposite to the reference-surface-side side face, where an obtuse angle is formed between the side face containing the anchor surface and a side face of the Y-direction portion adjacent to the side face.