| 摘要 |
PROBLEM TO BE SOLVED: To make a refractive index distribution uniform in a longitudinal direction and to make this distribution smooth in a radial direction by applying solns. prepd. by dissolving polymers and low-refractive index compds. into monomers on the circumference of a plastic rod and polymerizing these monomers, thereby forming polymer layers. SOLUTION: The polymer (polymethyl methacrylate) which is the center of the fiber is melt extruded to a fiber form and the soln. contg. the monomer as a solvent is applied on the surface of the fibrous polymer 10 by a coating applying nozzle 11. The polymer 10 coated with the soln. passing a UV irradiation region 21 is irradiated with UV rays from a UV source 11, by which the monomer is polymerized and solidified. This operation is successively repeated by the coating applying nozzles 12 to 15, the UV light sources 22 to 25 and the UV irradiation regions 32 to 35. The 60% polymers composed of methyl methacrylate and dibutyl sebacate are used as the first to fourth solns. |
