| 摘要 |
PURPOSE: To provide a low-loss optical waveguide and its production so that the difference in the refractive index between the clad and the core can be easily controlled and the loss does not increase even when the difference in the refractive index is made large. CONSTITUTION: This waveguide consists of a substrate 10, a lower clad layer 11 having low refractive index formed on the substrate 10, a core 12 formed on the lower clad layer 11, and an upper clad layer 13 which covers the core 12. In this optical waveguide, the lower clad layer 11 and the upper clad layer 13 consist of a SiO2 -base material with addition of a fluorine compd. |
