A semiconductor laser device.

摘要

A semiconductor laser device is disclosed which comprises a semiconductor substrate (1) and a multi-layered crystal structure disposed on the substrate (1), the multi-layered crystal structure containing a first cladding layer (3), a quantum-well active layer (5) for laser oscillation, and a second cladding layer (7) with a striped ridge portion (12) for current injection, wherein the difference in the effective refractive index between the region underneath the striped ridge portion (12) and the adjacent regions thereto is greater in the vicinity of at least one of the facets than inside of the facets.