Method of producing large polymer optical blanks with predictable axil refractive index profile
US6027672A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 31, 1997 |
| Grant date | Feb 22, 2000 |
| Priority date | — |
| Expiry date | Dec 31, 2017 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29K2995/0031
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
An apparatus and process are provided for depositing a polymeric element having a gradient in index of refraction that traverses the element from one surface to an opposite surface (axially graded refractive index). Two (or more) monomers are mixed in varying proportions and spray-deposited onto a substrate to form a layer. Each layer is then exposed to light to form a polymeric layer, and another layer deposited. Where the light is UV radiation and a light-sensitive catalyst that is also sensitive to the ambient atmosphere is used, then an inert gas dispenser, which provides an inert gas over the monomer layer, may be employed in conjunction with the UV radiation. Several layers are thus spray-deposited and exposed to light, each layer comprising a different mix of the two monomers, thereby providing each layer with a different index of refraction. After the prescribed number of layers has been deposited, the polymeric element is heat-treated to cause fusion of the layers and diffusion of components, thereby smoothing out the gradient profile. The apparatus and process of the invention are also useful in producing structural gradients in polymeric elements.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.