Antireflection film for plastic optical element
US5725959A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 22, 1996 |
| Grant date | Mar 10, 1998 |
| Priority date | — |
| Expiry date | Nov 22, 2016 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31667
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An antireflection film is procided on a plastic optical element as follows. An undercoat composed principally of unsaturated silicon exide SiO.sub.x (2>x>1) with a thickness within a range of 200 to 300 nm is formed on the optical element. A multi-layered film of a repeating structure is formed on the undercoat. The multi-layerd film has antireflective characteristics. The undercoat has a refractive index within a range of 1.49 to 1.59. The multi-layered film is composed of alternate lamination of a layer of a material which has a high refractive index and which is composed principally of TiO.sub.2, ZrO.sub.2 or a mixture thereof, and a layer of a material which has a low refractive index and which is composed principally of SiO.sub.x (2.gtoreq.x.gtoreq.1).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.