| 摘要 |
PURPOSE:To prevent the variation of the switch properties caused by the polarizing state of incident rays, by forming the directional coupling part with the distribution coupling parts exclusive for the TM mode and for the TE mode each. CONSTITUTION:The crystal layer 2 of the yttrium iron garnet or the like having the Faraday effect as well as a higher refractive index than the single-crystal substrate 1 is provided on the substrate 1 of the gallium gadolinium garnet or the like. In this case, the thickness of the layer 2 is increased partially to form an optical waveguide path. Then the propagation phase constant is set to beta, and the beta to the semi-TE and semi-TM modes of the waveguide path 3 is set identical to the beta to the semi-TM mode of the waveguide path 4 as well as to the beta to the semi-TE mode of the waveguide path 5 respectively. Thus the semi-TE mode light propagating the path 3 and the semi-TM mode light receive a distribution coupling at 4 and 5 each owing to the presence of the applied magnetic field 10 and are then radiated through the waveguide path 6. |
