Phase-shift distributed-feedback semiconductor laser

摘要

A phase-shift distributed-feedback semiconductor laser includes an electrode (6,7) for injecting a current to the entire area of the semiconductor laser. The laser also includes portions (4a′,4a) each for shifting an optical phase by a 1/4 wavelength at at least three locations, the number of which is an odd number. These portions (4a′,4a) are formed in a light propagation direction of the phase-shift distributed-feedback semiconductor laser structure.