| 摘要 |
PROBLEM TO BE SOLVED: To reduce influence of leakage light from an optical coupling structure.SOLUTION: An optical coupling structure includes a core, a first clad and a second clad. A refractive index of a material of the core is larger than a refractive index of a material of the first clad, and the refractive index of the material of the first clad is larger than a refractive index of a material of a second clad. The optical coupling structure maintains a first set of waveguide modes propagating mainly in the first clad in at least an input end, and a second set of higher-order waveguide modes separating from the first set of waveguide modes propagating mainly in the first clad in at least the input end.SELECTED DRAWING: Figure 5A |
