Yangtze Optical Fibre and Cable Company, Ltd.

Yangtze Optical Fibre and Cable Joint Stock Limited Company

Qingrong Han

Jie Luo

Chen Yang

Jing Li

Beibei Cao

Weijun Tong

Shuqiang Zhang

Yongtao Liu

Yuqing Cao

TieJun Wang

Fanghai Zhang

Raadjkoemar Matai

Raadj Matai

Matai Radjj

A method for manufacturing an optical fiber preform, including: a) providing a lining tube as a substrate tube, and doping and depositing by a PCVD or an MCVD process; b) in the reacting gas of silicon tetrachloride and oxygen, introducing a fluorine-containing gas for fluorine doping, introducing germanium tetrachloride for germanium doping, ionizing the reacting gas in the lining tube through microwaves to form plasma, depositing the plasma on the inner wall of the lining tube in the form of glass; c) after the completion of deposition, processing the deposited lining tube into a solid core rod by melting contraction through an electric heating furnace; d) sleeving the solid core rod into a pure quartz glass jacketing tube and manufacturing the two into an optical fiber preform; and e) allowing the effective diameter d of the optical fiber preform to become between 95 and 205 mm.

Methods for manufacturing optical fiber preform and methods for manufacturing optical fiber

A single mode fiber having a core, an inner cladding, a depressed cladding, and an outer cladding composed of pure silica glass. The core is surrounded in sequence with the inner cladding and the depressed cladding. The core has silica glass doped with germanium and fluorine, with a diameter (a) of 8.0-8.8 &#x3bc;m, a relative refractive index difference (&#x394;) of 0.35-0.38%, and the contribution of fluoride (&#x394;) is &#x2212;0.09&#xb1;0.02%. The inner cladding has silica glass doped with germanium and fluorine, with a diameter (b) of 18-21 &#x3bc;m and a relative refractive index difference (&#x394;) of 0&#xb1;0.02%. The depressed cladding has silica glass doped with fluorine, with a diameter (c) of 26-36 &#x3bc;m and a relative refractive index difference (&#x394;) at the external interface thereof is between &#x2212;0.22 and &#x2212;0.35%, and a relative refractive index difference (&#x394;) at the internal interface thereof is between &#x2212;0.20 and &#x2212;0.35%, and &#x394;&#x2266;&#x394;. The fiber has a good bending resistance, good mechanical properties, and extended service lifetime, and prevents the additional stresses generated by bending from passing on to the core, thereby reducing attenuation.

Single-mode fiber and production method thereof

A multimode fiber including a core and a cladding. The core has a radius (R) of 24-26 &#x3bc;m, the refractive index profile thereof is a parabola, and the maximum relative refractive index difference (&#x394;1) is 0.9-1.1%. The cladding surrounds the core and includes from inside to outside an inner cladding, a middle cladding, and an outer cladding; a radius (R) of the inner cladding is 1.04-1.6 times that of the core, and a relative refractive index difference (&#x394;2) thereof is &#x2212;0.01-0.01%; the middle cladding is a graded refractive index cladding whose radius (R) is 1.06-1.8 times that of the core, and a relative refractive index difference thereof is decreased from &#x394;2 to &#x394;4; and a radius (R) of the outer cladding is 2.38-2.63 times that of the core, and a relative refractive index difference (&#x394;4) thereof is between &#x2212;0.20 and &#x2212;0.40%. The invention reduces the additional bending loss of the fiber, improves the bending resistance and mechanical properties, basically eliminates the internal stress, and ensures the service life even working for a long term under the condition of low radius. The method for producing the fiber is simple, effective, and suitable for mass production.

Multi-mode bending-resistant fiber and production method thereof

The invention relates to a low dispersion slope dispersion-shifted single-mode fiber for large capacity transmission comprising a core and a cladding. Said fiber is characterized in that said core has three to five core segments having different refractive index profiles, and said cladding has four to six cladding segments. The total dispersion slope of said fiber at 1550 nm is less than 0.060 ps/nm&#xb7;km, the zero dispersion wavelength is less than 1420 nm, the effective area ranges from 55 &#x3bc;mto 65 &#x3bc;m, and the dispersion in the region of 1530 nm&#x2dc;1565 nm ranges from 5.0 ps/nm&#xb7;km to 12.0 ps/nm&#xb7;km. The fiber has low dispersion slope, moderate dispersion, low attenuation, and excellent bend resistance performance. It is suitable for a high-speed (10 Gbits/s and 40 Gbits/s), large capacity, and long distance DWDM system. Therefore, not only the non-linear problem that fazes high-speed communication is solved effectively, but also the DWDM transmission at 10 Gbits/s can be realized within a wider wavelength range. In addition, low dispersion slope is advantageous for comprehensive management of dispersion, so that the requirement for long distance non-electric relay can be fulfilled.

Dispersion-shifted single-mode fiber having low dispersion slope for large capacity transmission

Growing community of inventors

Wuhan, China

Qingrong Han