| 摘要 |
<p>PROBLEM TO BE SOLVED: To process propagating light after matching polarization to a TE wave or a TM wave through polarization conversion.SOLUTION: An optical element has an optical waveguide having a core and a cladding surrounding the core and having a refractive index that is no greater than 71.4% of a refractive index of the core. The optical waveguide includes; a polarization conversion unit 3 which receives conversion target light Lcontaining first and second light components C, Cof different polarization, converts the second light component into a third light component Chaving a different propagation mode order and the same polarization compared with the first light component C, and outputs converted light Lcontaining the first and the third light components; and an optical processing unit 5 which includes an output section 7 having a plurality of output ports 7-7and one or more multi-mode interference optical waveguides or planar optical waveguides, performs predetermined processing on the incoming converted light, and generates processed light Lcontaining the first and the third light components, whose propagation mode orders and an intensity ratio are kept identical to those of the converted light, at places where the output ports are connected.</p> |
