Patent ID: 6646775
Filing Date: 2003-11-11
Classification: H01S

Abstract:
An optical device comprising:a substrate; a distributed feedback (DFB) semiconductor laser formed on the substrate and including a diffraction grating having an asymmetrical &lgr;/4 phase shift region, the diffraction grating extending along an optical axis of the DFB semiconductor laser; and a field absorbing modulator integrated with the DFB semiconductor laser on the substrate for modulating a light wave emitted from the DFB semiconductor laser, the field absorbing modulator having a facet reflection rate between 0.01 and 0.02% at an output end thereof, the diffraction grating having a &kgr;L value between 1 and 1.2, wherein &kgr; is a mode coupling constant, and L s a cavity length of the DFB laser.