摘要 |
A semiconductor laser device including a first semiconductor layer having a strip waveguide structure to obtain optical confinement and a second semiconductor layer having a ridge waveguide structure for defining an electrical current passage region. The strip waveguide structure has a first width, and projects on the first semiconductor layer, extending over the central area of the layer in a longitudinal direction. The ridge waveguide structure projects on the second semiconductor layer and extends in the longitudinal direction with a second width which corresponds to the strip structure. The strip waveguide structure cooperates with the ridge waveguide structure to produce a difference between the refractive index of a center region which extends in the longitudinal direction of the second semiconductor and that of a neighboring region due to the difference in thicknesses between the two, so that the center region serves as an optical waveguide. |