Anti-glare filter
US4697881A · kind A · utility
10Cited by
19References
15Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Apr 23, 1985 |
| Grant date | Oct 6, 1987 |
| Priority date | — |
| Expiry date | Apr 23, 2005 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B5/045
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A filter for reducing the glare of a viewing screen caused by ambient light is comprised of a substantially transparent sheet of material having first and second faces. The first face is substantially planar while the second face has a plurality of V-shaped grooves, each groove being formed by two walls. The geometry of the V-shaped grooves is such that ambient light enters the filter and becomes trapped therein due to internal reflection.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.