| 摘要 |
PURPOSE:To prevent the coupling loss by the mismatching of an electric field distribution of light by providing glass which is nearly the same in refractive index as clad glass but is largely different in coefft. of thermal expansion therefrom on both sides of core glass as a stress imparting part. CONSTITUTION:This optical waveguide is constructed by forming a core 11 and the stress imparting part 21 on a quartz substrate 13 and embedding the circumference thereof with the clad 12. The core 11 is SiO2-TiO2 glass, the stress imparting part 21 is P2O5-B2O3-SiO2 glass, and the clad 12 is SiO2 glass. The refractive index of the stress imparting part 21 is equalized to the refractive index of the clad 12 by adjusting the compsn. ratio of the P2O5 and B2O3. The polarization maintaining property is enhanced in this way and the connection of the waveguide to an ordinary single-mode optical fiber is possible without increasing the coupling loss by the mismatching of the electric field distribution of light. |
