| 摘要 |
PURPOSE:To stabilize light transmitting characteristics of optical fiber by providing a second plastic clad having high refractive index to the outside of a plastic clad of optical fiber comprising plastic clad and quartz glass core. CONSTITUTION:A plastic clad 3 having higher refractive index than the refractive index of a plastic clad 2 which forms optical fiber comprising a quartz glass core 1 and the plastic clad 2, is provided to the outside of the plastic clad 2. Since the light leaked out into the plastic cord 2 transmits the second plastic clad 3 and is converted to leaky light, propagated light of higher order mode is eliminated, and propagated light of lower mode only is concentrated in the quartz glass core 1 and propagated. By this constitution, the propagated light is not influenced by the plastic clad 2, so the light transmitting characteristics of the optical fiber are stabilized. |
