| 摘要 |
PURPOSE:To provide the light intensity modulator, which does not require any DC bias, by using a 1X2 directional coupling 3dB coupler for the waveguide type Mach-Zender light intensity modulator. CONSTITUTION:Concerning the waveguide type Mach-Zender light intensity modulator, branch on the side of an input waveguide 6 is constituted as a directional coupling 3dB coupler 4 composed of linear waveguides 4a and 4b, and branch on the side of an output waveguide 7 is constituted as a Y branch 5. Even when the branch on the side of the input waveguide 6 is constituted as the Y branch and the branch on the side of the output waveguide 7 is constituted as the directional coupling 3dB coupler, because of the reciprocity of an optical circuit, functions as the light intensity modulator are not changed. An LiNbO3 substrate 1, SiO2 buffer layer 2, upper and lower waveguides 8a, 8b and upper and lower electrodes 3a, 3b are provided as other components. |
