| 摘要 |
PROBLEM TO BE SOLVED: To provide a semiconductor laser which can improve the maximum output with a simple constitution by restraining effectively generation of beam staring. SOLUTION: A stripe type optical waveguide which is formed including an active layer 4 and a second clad layer 8 and functions as a resonator is arranged on a semiconductor substrate 1. The waveguide includes a narrow stripe type fundamental mode waveguide part on an end surface 32 side, a wider stripe type multimode waveguide part on an output end surface 31 side, and a tapered part combining them. A current non-injection part 8a is formed in the second clad layer 8, as a current injection restraining means which restrains current injection into the active layer 4 in at least a part of the fundamental mode waveguide part, and is covered with a current blocking layer 10. |
