Patent ID: 9726817
Date: 2017-08-08
CPC Classifications: C03B,C03C,G02B,G02F

Claim:
1. A small-diameter polarization maintaining optical fiber, comprising quartz optical fiber ( 5 ), the periphery of the quartz optical fiber ( 5 ) is provided with an inner coating ( 6 ) and an outer coating ( 8 ), the inner of the quartz optical fiber ( 5 ) is provided with an optical fiber core layer ( 1 ) and a quartz cladding ( 2 ), the quartz cladding ( 2 ) is located at the periphery of the optical fiber core layer ( 1 ); two stress zones ( 4 ) are provided between the optical fiber core layer ( 1 ) and the quartz cladding ( 2 ), the two stress zones ( 4 ) are symmetrically distributed along the center of the optical fiber core layer ( 1 ); characterized in that: a buffer coating ( 7 ) is provided between the inner coating ( 6 ) and the outer coating ( 8 ), the periphery of each stress zone ( 4 ) is provided with a buffer layer ( 3 ) which is concentric with the stress zone ( 4 ); the refractive index of the optical fiber core layer ( the relative refractive index difference Δn when working wavelength of the small-diameter polarization maintaining optical fiber is 1310 nm, its attenuation is below 0.5 dB/km, and its crosstalk reaches −35 dB/km; when working wavelength of the small-diameter polarization maintaining optical fiber is 1550 nm, its attenuation is below 0.4 dB/km, and its crosstalk reaches −30 dB/km.