| 摘要 |
PURPOSE:To make the refractive index of a clad layer uniform in a glass waveguide. CONSTITUTION:This glass waveguide having a clad layer is produced by forming cores 1 on a silica glass substrate 4 or on a silicon substrate on which silica glass is formed, depositing porous clad layers to cover the cores 1, and then changing the porous clad layers into transparent glass. The first porous clad layer 2 which covers the cores does not contain no P2O5 but contains B2O3, while the second porous clad layer 3 which covers the first porous clad layer 2 contains both of P2O5 and B2O3. Thereby, a glass clad layer having uniform refractive index can be formed in the finish state after diffusion. |
