DISTRIBUTED FEEDBACK SEMICONDUCTOR LASER INTERGRATED WITH MONITOR

摘要

A distributed feedback semiconductor laser with a monitor, which has periodic corrugations on a light emitting layer or an adjoining layer in the direction of travel of light and performs laser oscillation by the injection of a current into said light emitting layer. In accordance with the present invention, a laser region forming said distributed feedback semiconductor laser and a monitor region for detecting the output of said laser region are disposed on the same substrate. A gap between said monitor region and said laser region is filled with a semiconductor of an energy bandgap larger than that of the light emitting layer of said laser region.