TH50797A - Optical fibers and optical communication systems that use this type of fiber - Google Patents

Abstract

DC60 (03/12/44) This invention deals with optical fibers capable of forming a light transmission line. For the transmission, multiplexing, wavelength division in the wavelength band of 1.5 (formula) m, using a Raman amplifier and optical communication system using this fiber. Optical fiber has Effective core area from 40 (formula) m2 to 60 (formula) m2 in the carefully set wavelength band. The least one of the wavelength bands of 1.5 (formula) m; Dispersion values from 4 to 10 ps / nm / km at a wavelength of 1.55 (formula) m; The slope of the distribution Set at a positive value equal to or less than 0.4 ps / nm2 / km in the wavelength band of 1.55 (formula) m; And the wavelength at zero distribution is equal to or less than 1.4 (formula) m. In addition, the cutoff wavelength Is set to be equal to or less than 1.5 (formula) m at a length of 2 m and the curvature loss It is set to be equal to or less than 5 dB / m at a diameter of 20 mm in the wavelength band of 1.5 (formula) m in the refractive index profile of the optical fibers, for example the difference of the relative refractive index (formula) 1. Of the first glass layer To be the innermost layer compared to the reference layer And difference of the relative refractive index (formula) 3 of the third glass layer To be the third layer From the side in In addition, the difference of the refractive index (formula) 2 of the second glass layer was set to be positive. To be the floor that Two from the side in Compared to the reference class Is set to negative The invention deals with optical fibers capable of forming optical transmission lines. For the transmission, multiplexing, wavelength division in the wavelength band of 1.5 m m, using a Raman amplifier and optical communication systems using this fiber. Optical fiber has Effective core area from 40 mu m2 to 60 mu m2 in the carefully set wavelength band. The least one of the band's wavelengths of 1.5 mu m; Dispersion values from 4 to 10 ps / nm / km at a wavelength of 1.55 mu m; The slope of the distribution Set at a positive value equal to or less than 0.4 ps / nm2 / km in the wavelength band of 1.55 mu m; And the wavelength at zero distribution is equal to or less than 1.4 mu m. Is set to be equal to or less than 1.5 mu m at a length of 2 m and the curvature loss Is set to be equal to or less than 5 dB / m at a diameter of 20 mm in the wavelength band of 1.5 m m in the refractive index profile of the optical fibers, for example the difference in the relative refractive index delta 1 of First glass shelf To be the innermost layer compared to the reference layer And difference of delta 3 relative refractive index of the third glass layer. To be the third layer From the side in Compared with the reference class is set to positive. Difference of Delta II refractive index of the second glass layer. To be the floor that Two from the side in Compared to the reference class Is set to negative

Claims (1)

1. Optical fibers consist of: Effective core area from 40 mu m2 to 60 mu m2 in the set wavelength band. Of at least part of the wavelength band of 1.5 mu m; Dispersion value set at 4 ps / mn / kw or more and at 10 ps / mn / kw or less at Wavelength of 1.55 mu m; The slope of the distribution Set At a positive value Equal to or less than 0.04 ps / nm2 / kw in the wavelength band of 1.55 mu m; And the wavelength at zero distribution