| 摘要 |
PROBLEM TO BE SOLVED: To reduce loss due to a microbend and to reduce the generation of a nonlinear phenomenon by specifying the absolute value of wavelength dispersion in a specified wavelength to a specified value and specifying the value of a specified parameter to the specified value. SOLUTION: In the dispersed shift optical fiber, the ring-like area of a refractive index n2 is provided around the center area of the refractive index n1 and the clad area of the refractive index n3 is provided around it. With the refractive index n3 of the clad area as a standard, the specific refractive index difference of the center area is -0.4% and the specific refractive index difference of the ring-like area is +1.2%. Relating to the dispersed shift optical fiber, at the wavelength 1550 nm, the absolute value of the wavelength dispersion is <=5 ps/nm/km. Also, based on a mode field radius w01 and an effective cross section area Aeff defined by Petermann-I, the value of the parameter k01 defined by k01 =Aeff/(π.w01 <2> ) is >=0.8. |
