High performance dispersion compensating optical fibers and manufacturing method for the same

Abstract

A high performance dispersion compensating optical fiber is provided. In one embodiment, the optical fiber includes a core layer and a cladding layer surrounding the core layer. The core layer includes five core sublayers wherein the □ % of the first core sublayer is positive, and the □ % of at least one of the other core sublayers is negative, the radius ranges of the respective core sublayers beginning outwardly from the first core sublayer are 0.6 to 0.8 μm, 1.0 to 1.2 μm, 1.6 to 2.0 μm, 5.0 to 6.0 μm, and 7.0 to 8.0 μm, respectively; the ranges of □ % of the respective sublayers beginning outwardly from the first core sublayer are about 1.8 to 2.1%, 1.2 to 1.4%, 0.6 to 1%, −0.4 to −0.6% and 0.2 to 0.4%, and the cladding layer is a pure Silicon Dioxide glass layer.

1 . A high performance dispersion compensating optical fiber, comprising a core layer and a cladding layer surrounding the core layer, the core layer comprising five core sublayers, characterized in that the Δ % of the first core sublayer is positive, and the Δ % of at least one of the other core sublayers is negative, the radius ranges of the respective core sublayers beginning outwardly from the first core sublayer are 0.6 to 0.8 μm, 1.0 to 1.2 μm, 1.6 to 2.0 μm, 5.0 to 6.0 μm, and 7.0 to 8.0 μm, respectively; the ranges of Δ % of the respective sublayers beginning outwardly from the first core sublayer are about 1.8 to 2.1%, 1.2 to 1.4%, 0.6 to 1%, −0.4 to −0.6% and 0.2 to 0.4%, and the cladding layer is a pure Silicon Dioxide glass layer.  
   
   
       2 . A high performance dispersion compensating optical fiber as cited in  claim 1 , characterized in that a sixth core sublayer is disposed outside said five core sublayers, the radius range of the sixth core sublayer is about 9.0 to 10.0 μm, the range of Δ % of the sixth core sublayer is about −0.2 to −0.4%.  
   
   
       3 . A high performance dispersion compensating optical fiber as cited in  claim 1 , characterized in that the attenuation at 1545 nm is not greater than 0.4 dB/km, the attenuation in the wavelength range of 1525 nm˜1565 nm is not greater than 0.5 dB/km; the Figure of Merit at 1545 nm is greater than 350 ps/nm.dB, and the dispersion coefficient at C band (1525 nm˜1565 nm) is −90˜−200 ps/nm.km.  
   
   
       4 . A high performance dispersion compensating optical fiber as cited in  claim 1 , characterized in that it has a negative dispersion slope at C band (1525 nm˜1565 nm), the dispersion slope being −0.4˜−1.0 ps/nm 2  km at 1545 nm.  
   
   
       5 . A high performance dispersion compensating optical fiber as cited in  claim 1 , characterized in that the relative dispersion slope is 0.0030 nm −1 ˜0.0044 nm −1 .  
   
   
       6 . A high performance dispersion compensating optical fiber as cited in  claim 1 , characterized in that the polarization mode dispersion reaches 0.1 ps/km 1/2 .  
   
   
       7 . A high performance dispersion compensating module, characterized in that the dispersion compensating optical fiber in the dispersion compensating module is formed by the dispersion compensating optical fiber described in  claim 1 .  
   
   
       8 . A method for manufacturing a high performance dispersion compensating optical fiber, comprising: depositing on the inner wall of a substrate tube by using PCVD process a layer having a particular structure design; collapsing the substrate tube to form a solid core rod according to a collapsing process; combining the core rod and a low hydroxyl sleeve tube by a RIT process to form an optical fiber preform, or producing an optical fiber preform by depositing an outer cladding layer on the outer surface of the core rod; and sending the optical fiber preform into a fiber-drawing furnace for drawing it to form a fiber, characterized in that: 
 freon (C 2 F 6 ) is doped in the process for depositing the core rod to realize the deposition of the trench sublayer around the optical fiber core, and a large size optical fiber preform manufacturing technology in which the diameter of the optical fiber preform reaches  80  mm-l  60  mm is used, then the large size preform is stretched to a preform having a small diameter by using a stretching process, and then sending it into a fiber-drawing furnace for drawing it to optical fiber.    
   
   
       9 . A method for manufacturing a high performance dispersion compensating optical fiber as cited in  claim 8 , characterized in that the diameter of the small diameter preform after stretching is 60 mm˜30 mm.  
   
   
       10 . A method for manufacturing a high performance dispersion compensating optical fiber as cited in  claim 8 , characterized in that in the refractive index structure of the optical fiber, the contribution to the refractive index of the freon doped trench core sublayer is −0.4% to −0.9%.  
   
   
       11 . A method for manufacturing a high performance dispersion compensating optical fiber as cited in  claim 8 , characterized in that freon (C 2 F 6 ) is doped in a part of the cladding layers.