| 摘要 |
PROBLEM TO BE SOLVED: To impart a sufficient numerical aperture to the optical fiber, to lower loss and to decrease the degree of the fall of the glass transition temp. of the optical fiber. SOLUTION: This optical fiber is so formed that the concn. of high-refractive index non-polymerizable compds. decreases in the outer peripheral part direction from the central part of the fiber consisting of a transparent matrix polymer and the concn. of low-refractive index non-polymerizable compds. decreases from the outer peripheral part toward the central part. The optical fiber is obtd. by discharging the plural spinning raw liquids which consist of the polymer or further its constituting monomer, the high-refractive index non-polymerizable compds. and the low-refractive index non-polymerizable compds. and vary in the respective compsn. ratios of the high-refractive index non-polymerizable compds. and the low-refractive index non-polymerizable compds., in a concentrically laminated state by using a multilayered composite spinning nozzle, and further, interdiffusing at least these non-polymerizable compds. between the adjacent layers under heating. |
