| 摘要 |
PURPOSE: To produce an optical waveguide formed so that a part of high refractive index is widened in the vicinity of incident end. CONSTITUTION: A 1st selective ion exchange is executed after a mask 51 is applied on the surface of a substrate 50. Successively a mask 52 opening only in the vicinity of a position to be the incident end of the optical waveguide is formed on the substrate 50 and a 2nd selective ion exchange is executed. Next, the ion-exchanged part formed on the substrate 50 is changed to the part of high refractive index by heat treating to form the optical waveguide. The depth of the ion-exchanged part formed by the 2nd ion exchange is deeper than another part and then, the part of high refractive index at the incident end is widened. |
