| 摘要 |
PURPOSE:To separate on optical signal by polarized light by providing a 2nd optical waveguide which has a start point part arranged nearby a halfway part of a 1st optical waveguide on a transparent substrate, and providing a uniaxial crystal plate which has its optical axis slanting to the optical axis of the waveguide. CONSTITUTION:On an optical glass substrate 1, the 1st waveguide 10 and 2nd waveguide 20 each has a single mode are formed and a groove 2 where a calcite plate 3 is inserted is formed. The 2nd waveguide 20 has two curved parts and its start point part 21 is arranged nearby the center part of the 1st waveguide 10 in parallel. The optical axis of the calcite plate 3 slants to the normal line of its parallel end surface and the plane determined by the optical axis and normal coincides with the plane of the substrate 1. Here, the light signal is propagated in the 1st waveguide 10 to travel straight in TM mode which has an electric field perpendicular to the surface of the substrate 1, but travel slantingly in the calcite plate 3 in TE mode having a parallel electric field, and is propagated in the 2nd waveguide 20. Consequently, the projection light from an optical fiber is separated by polarized light. |
