| 摘要 |
PURPOSE:To make an elliptical formation of clad and a core formation easy in a titled fiber, by specifying the total doping amount of P2O5 and B2O3 of a clad consisting of P2O5-B2O3-SiO2 glass. CONSTITUTION:A clad 2 consisting of SiO2 in high purity has a smaller refractive index than a core 1 and has a clad 3 which has a smaller refractive index than the core 1 and a larger index than the clad 2 and has an elliptical section, at its outer circumference. Further, a clad 4 having a smaller refractive index than the clad 3 is provided at its further outer circumference. The clad 3 consists of P2O5-B2O3-SiO2 glass and the total doping amount of the P2O5 and B2O3 is regulated to 8-15mol%. By such a setting, a proper hardness is obtained and a formation of the ellipse of the clad 3 and a formation of the core 2 are performed easily in manufacture. |
