| 摘要 |
PURPOSE:To obtain a large-scale and multifunctional integrated optical device by a method wherein diffraction gratings in different semiconductors are installed in positions which can be optically coupled to each other by diffracted beams by means of the diffraction gratings. CONSTITUTION:From a beam generated by a distributed Bragg reflection type laser (composed of an active layer 7, a waveguide 3b and a diffraction grating 2b) formed at the upper part, a beam diffracted in a direction perpendicular to a resonance direction by means of the second-order diffraction grating with reference to the laser beam is radiated. The diffracted beam radiated downward is optically coupled to an underside diffraction grating 2a through a modulation layer 5; the beam is guided to the underside waveguide 3a. In this case, the beam is guided simply to the underside waveguide 3a; the beam is radiated from its end face; intensity of the radiated beam is modulated by the modulation layer 5; even with this structure, if a filter, an amplifier and a phase modulator are formed at a tip part of the underside waveguide 3a, it is easy to realize a more multifunctional integrated device. |
