| 摘要 |
<p>This optical fiber is provided with a central core, a side core and a cladding. The periphery of the central core includes a ring portion in which the relative refractive index difference changes discontinuously. Defining a as the radius from the core center to outside of the ring portion, and c as the radius up to the position where the relative refractive index difference is maximal in the side core, by realizing a refractive-index distribution of a shape in which c/a is 2.25 to 2.50, the variance value, cable cut-off wavelength, bending loss at a diameter of 20mm, and effective cross-sectional area can be configured in a desired range.</p> |
