OPTICAL WAVEGUIDE ELEMENT

摘要

PROBLEM TO BE SOLVED: To provide an optical waveguide element in which optical waveguide cores having different thicknesses can be connected.SOLUTION: The optical waveguide element includes a first optical waveguide core 30 and a second optical waveguide core 40 having different thicknesses from each other. A coupling region 50 is set where the first optical waveguide core and the second optical waveguide core are juxtaposed as spaced from each other. In the coupling region, each of the first optical waveguide core and the second optical waveguide core has a width in which a propagation constant of TE polarized waves propagating in the first optical waveguide core coincides with a propagation constant of TE polarized waves propagating in the second optical waveguide core, and also has a width in which a propagation constant of TM polarized waves propagating in the first optical waveguide core coincides with a propagation constant of TM polarized waves propagating in the second optical waveguide core.SELECTED DRAWING: Figure 1