Process for obtaining a transparent article with a refractive index gradient
US5807906A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 27, 1996 |
| Grant date | Sep 15, 1998 |
| Priority date | — |
| Expiry date | Feb 27, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02C2202/12
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
Process for obtaining a transparent article with a refractive index gradient, including the steps of: (1) irradiating a crosslinkable liquid mixture of base photopolymerizable monomers which is modulated spatially in intensity and/or irradiation time to form a structure gradient according to a desired index profile until a self-supporting polymer matrix is obtained; (2) swelling the polymer matrix to thermodynamic equilibrium in a swelling composition containing a polymerization initiator and one or several polymerizable monomers producing a polymer of different refractive index from the refractive index of the matrix obtained in step (1); and (3) polymerizing the swelling composition which has diffused into the matrix homogeneously, thereby obtaining a transparent article with a refractive index gradient.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.