POLARIZATION MAINTAINING OPTICAL FIBER

摘要

PURPOSE:To easily obtain a core which as large ellipticity by forming a single waveguide part of cores which are arranged in a clad and have a larger refracting index than the clad. CONSTITUTION:The single waveguide part consists of the cores 11 and 12 which are arranged in the core 13 and have the larger refractive index than the clad 13. The waveguide part (x) is high in refractive index on an average in (x)- polarization mode and low in mean refractive index in (y)-polarization mode. Consequently, the refractive indexes corresponding to both polarized components are different to cause double refraction. Namely, the (x)-directional propagation constant betax is not equal to the (y-directional propagation constant betay and the components in both polarization modes can not be coupled and are propagated without interfering with each other. Consequently, an optical fiber corresponding to an elliptic core type polarization maintaining fiber which has large ellipticity can easily be obtained.