| 摘要 |
PURPOSE:To reduce the restrictions of a substrate, to facilitate the formation of an optical waveguide, and to realize low cost and high performance by laminating a core layer which performs wavelength conversion by nonlinear optical effect, a 1st clad layer which has a higher refractive index than the core layer, and 2nd clad layer which has a lower refractive index than the 1st clad layer. CONSTITUTION:Light which is incident on the core layer 2 is reflected totally by the 1st clad layer 3, leaking light causes interference in the 2nd clad layer 4, and the light is confined to the core layer 2 in single mode. At the same time, higher harmonics which are wavelength-converted by the core layer 2 which has nonlinear optical effect are emitted to the 2nd clad layer 4 or optical waveguide provided separately to enable phase matching which is stable and excellent against temperature variation. Further, the confinement efficiency of a basic wave to the core layer 2 is good and the leak is small, so the light power density is improved and the wavelength conversion efficiency is improved. Consequently, the excellent optical waveguide is easily formed at low cost. |
