| 摘要 |
PROBLEM TO BE SOLVED: To provide a grating coupler having good controllability of an output electric field intensity profile while avoiding difficulties in production.SOLUTION: A grating coupler in which grooves are formed on a surface layer of an optical waveguide 103 on a substrate 101 couples light propagating through the optical waveguide and light emitted to the outside or propagating through the outside of the optical waveguide with the optical waveguide 103, in an area formed with the grooves within the optical waveguide. The grooves are repeatedly formed in the longitudinal direction of the optical waveguide 103 on the surface layer of the optical waveguide 103, and the widths of the grooves are made narrower than the width of the optical waveguide. |
