Phase-shifted distributed feedback type semiconductor laser device.

摘要

A semiconductor laser device has a periodic structure for distributively feeding back light. A waveguide (18) for guiding light along the periodic structure is provided. A plurality of waveguide regions (4, 5) having a light confinement coefficient set to vary along the periodic structure and an equivalent amount of phase shift with respect to the phase of the periodic structure set to an integer multiple of pi are provided. The total phase shifting amount of light by the waveguide (18) is set to a value different from an integer multiple of pi . <IMAGE> <IMAGE>