| 摘要 |
PURPOSE:To make the production of a lightweight and flexible focusing type optical transmission body easy by irradiating light of two or more kinds of wavelengths to a preform member comprising a photopolymerization plastic of a fine bar shape of refractive indexes decreasing with progression of polymerization from the outside circumferential direction toward the central axis. CONSTITUTION:The homogeneous plastic which comprises essentially, for example, polycarbonate Z of refractive indexes decreasing with an increase in the degree of polymerization and in which methyl acrylate, a sensitizer and a light absorbing control agent and an antifogging agent are dissolved is used for the photopolymerization plastic. This is molded to a preform rod, which is then spun by a heating and drawing device. The thus spun fiber is irradiated by light such as Hg 870nm (lambda1) and N2 laser 337nm (lambda2) from the outside circumference toward the central axis. Thence, methyl acrylate is removed. This yields the optical transmission body of refractive indexes increasing toward the inner side. Thereby, the lightweight and flexible focusing type optical transmission body may be easily obtained. |
