Semiconductor optical amplification element

摘要

A semiconductor optical amplification element has an optical waveguide which includes a core layer formed from an active layer (12; 21; 31; 41; 51; 61; 74) acting as an optical amplification medium and amplifies and outputs an optical signal without electrically converting the optical signal. The light reflection factor on an inputting side end of the element for the optical signal is lower than the light reflection factor on another outputting side end of the element. <IMAGE>