MANUFACTURE OF TRANSPARENT ARTICLE WITH REFRACTIVE INDEX GRADIENT

摘要

PROBLEM TO BE SOLVED: To obtain a uniform refractive index in a simple optical system by irradiating a crosslinkable mixed soln. of a photopolymerizable monomer according to refractive index distribution until a polymer having self-shape holdability is obtained, and swelling this polymer in a swelling compsn. containing a monomer forming a polymer having a different refractive index to uniformly polymerize the swelling compsn. dispersed in a matrix. SOLUTION: A crosslinkable liquid mixture of a photopolymerizable monomer is irradiated according to desired refractive index distribution while regulating intensity and/or irradiation time until a polymer having self-shape holdability is obtained. This polymer is swollen along with a polymn. initiator in a swelling compsn. containing a polymerizable monomer forming a polymer having a refractive index different from that of the obtained polymer of a fundamental matrix up to thermodynamic equilibrium. Next, the swelling compsn. dispersed in the matrix is uniformly polymerized so as to obtain a final article having a refractive index gradient. The mixture of the photopolymerizable fundamental monomer contains a monofunctional monomer and a polyfunctional crosslinking agent.