| 摘要 |
PROBLEM TO BE SOLVED: To obtain a polarization modulation semiconductor laser capable of a wide range of polarization modulation operation and a relatively low cost by constituting the device by using a TE mode semiconductor laser structure and a TM mode semiconductor laser structure which can be optimized practically independently. SOLUTION: Two different semiconductor laser structures 1, 2 are arranged in series in a waveguide direction in a composite resonator type semiconductor laser. One semiconductor laser structure 1 has an active region which predominates in gain of one polarization mode, and a distributed feed back type resonator or a distributed Bragg reflection type resonator or a Fabry-Perot resonator. The two semiconductor laser structures 1, 2 are arranged with a clearance 3 in a waveguide direction. |
