A semiconductor laser device includes an active layer configured to radiate
light, a light reflecting facet positioned on a first side of the active
layer, and a light emitting facet positioned on a second side of the
active layer thereby forming a resonator between the light reflecting
facet and the light emitting facet. A diffraction grating is positioned
within the resonator along a portion of the length of the active layer and
the laser device is configured to operate as a multiple mode oscillation
device. A window structure is provided between an end of the active layer
and one of the light reflecting and light emitting facets, and the window
structure is configured to reduce a reflectivity of the one of the light
reflecting and light emitting facets.
