| 摘要 |
PURPOSE:To externally condense the oscillated light of a semiconductor laser through a waveguide by a second diffraction grating thereby to oscillate it in a single vertical mode to perform a stable operation of single condensed spot by integrating the laser having a first diffraction grating and a two-dimensional optical wave guide having the second diffraction grating on a semiconductor substrate. CONSTITUTION:An optical integrated circuit has an n-type GaAs substrate 11, an n-type AlGaAs clad layer 12, a first diffraction grating 13, an n-type AlGaAs optical wave guide 14, an n-type GaAs active layer 15, a p-type AlGaAs clad layer 16, a P<+> type GaAs cap layer 17, a second diffraction grating 19, and an AlGaAs two-dimensional optical wave guide 20. The grating 19 is formed concentrically at the emitting end of a laser 18 as a center, and a pitch is increased toward the center. The laser light of a single vertical mode irradiated from the laser 18 is conducted through the optical wave guide 20 to be condensed at the top of the substrate 11 by the grating 19 to form a single spot. |
