OPTICAL SWITCH

PURPOSE:To enable the normal switching operation of a light transmission path performed by the existence of applied voltage to a first electrode in the connected region of two light waveguide paths by forming a second electrode around the input part of either one of two light waveguide paths. CONSTITUTION:In the connected region X of two light waveguide paths 2, 3, a second electrode 18 is formed around the input part of either light waveguide path, the light waveguide path 2, for instance. When high frequency voltage is applied to the second electrode 18, a light signal passing this part is changed in phase so as to have equivalent wavelength change. Accordingly, even if light signals of the same wavelength are inputted into two light waveguide paths 2, 3, both light signals do not interfere strongly with each other in the connected region X of the light waveguide paths 2, 3. The switching of a light transmission path performed by the existence of applied voltage to a first electrode 17 can be performed normally.