| 摘要 |
PURPOSE:To make the driving circuit simple and to drive the circuit with a low voltage by providing buried type 1st electrodes for controlling polarized light in parallel with the surface of an waveguide substrate on both sides of optical waveguides and the 2nd electrodes for controlling polarized light perpendicularly to the surface of the substrate. CONSTITUTION:Buried electrodes 16, 18, and 20 for controlling light having electric field amplitudes and TE mode light are formed respectively on both sides of parallel waveguide sections 12a and 14a in parallel with the sections 12a and 14a and, at the same time, in parallel with the surface of an LN substrate 11. In addition, electrodes 22 and 24 for controlling light having electric field amplitudes and TM mode light are formed on the sections 12a and 14a perpendicularly to the surface of the substrate 11. When the ratio of the lowest voltage for making TE-polarized light extinct to the lowest voltage for making TM mode light extinct in represented by N, an optical switch 10 can be driven against both TE- and TM modes light by applying the same voltage across both sets of the electrodes for control from a common power source 26 by making the lengths of the electrodes 16, 18, and 20 equivalent to those of the sections 12a and 14a and the lengths of the electrodes 22 and 24 1/N of the those of the sections 12a and 14a. |
