PANDA POLARIZATION MAINTAINING OPTICAL FIBER

摘要

Disclosed is a PANDA polarization maintaining optical fiber, comprising a core layer (1) and quartz cladding (2), wherein two stress regions (3), which are centrosymmetric along the core layer (1), are provided in the quartz cladding (2), and transition annular regions (4), which are concentric with the stress regions (3), are provided outside the stress regions (3); the core layer (1) comprises a germanium-doped core layer (10) and a fluorine-doped core layer (11) successively arranged from the inside to the outside; the germanium-doped core layer (10) comprises a flat germanium-doped layer (100) and a gradient germanium-doped layer (101) successively arranged from the inside to the outside; the refractive index profile of the gradient germanium-doped layer (101) is of a parabolic shape, and the refractive index of the gradient germanium-doped layer (101) gradually decreases in a direction away from the flat germanium-doped layer (100); the fluorine-doped core layer (11) comprises a quartz core layer (110), a first gradient fluorine-doped layer (111), a flat fluorine-doped layer (112) and a second gradient fluorine-doped layer (113) successively arranged from the inside to the outside; the refractive index profiles of the first gradient fluorine-doped layer (111) and the second gradient fluorine-doped layer (113) are both in the shape of a curve, and are symmetric along the refractive index profile of the flat fluorine-doped layer (112); and the refractive index of the first gradient fluorine-doped layer (111) gradually decreases in a direction away from the quartz core layer (110). The cut-off wavelength of the polarization maintaining optical fiber is less than 830 nm. The PANDA polarization maintaining optical fiber is applicable to multiple bands and has a good attenuation and a good extinction ratio.