A semiconductor laser device have, on a substrate, a semiconductor layer
including an active layer sandwiched between an n-type layer and a p-type
layer, the semiconductor layer having a sonator face formed by etching
and a projection projecting out in an emission direction relatively to
the resonator face, wherein a protective film is formed to extend from
the resonator face to an end face of the projection, and, an emission
critical angle, which is the largest angle at which light emitted from
the resonator face can be radiated without being blocked by the
projection and the protective film formed on the projection, is larger
than an emission half-angle of an emission distribution in a vertical
direction of a laser beam emitted from the resonator face.