| 摘要 |
PURPOSE:To enable oscillations at a stable single longitudinal mode by forming a diffraction grating to the whole resonator and shaping three or more of electrodes capable of independently adjusting the quantity of currents injected in the direction of an optical axis. CONSTITUTION:A diffraction grating 10 is formed extending over the whole resonator, and three injection electrodes 11, 12, 13 are shaped separated in the axial direction. When the quantities of currents injected to several electrode 11-13 are changed and the distribution of carrier density is formed in a resonator, the distribution of refractive indices can be shape in the direction of the resonator by the changes of refractive indices by carrier density. The optical pitches of the diffraction grating are altered in the direction of the resonator by the distribution of the refractive indices, thus acquiring the same effect as the formation of a diffraction grating, intervals thereof vary through electron- beam exposure, etc. |
