| 摘要 |
PURPOSE:To provide a light waveguide in which the max. number of modes in the width and depth directions can easily be set in an optional value. CONSTITUTION:A first diffusive material is diffused in the regions 4, 3a, 3b of a substrate 1 to give higher refractive index in these regions 4, 3a, 3b than in the substrate 1. Then a second diffusive material is diffused in the regions 3a, 3b, 3c, 3d to give higher refractive index to these regions than the refractive index before diffusion. The refractive index in the regions 3a, 3b is made lower than in the region 4. Thereby, a light waveguide consisting of the region 4 as the core and the regions 3a, 3b, 1a as a clad is formed. |
