Transparency viewing apparatus
US6088941A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 6, 1992 |
| Grant date | Jul 18, 2000 |
| Priority date | — |
| Expiry date | Apr 6, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B27/024
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Viewing apparatus including a viewing surface having a viewing area, back-lighting apparatus for selectably adjusting the back-illumination of areas of the viewing surface, the areas having a given extent, the back-lighting means including: an liquid crystal array of individually controllable liquid crystal light attenuators located behind the viewing surface, each element of the array being associated with an area of the viewing surface and including active elements having a controllable opacity over an area smaller than the given extent of the area with which it is associated, and inactive areas between the active elements, a light source behind the array of light attenuators and a plurality of light guides, each associated with an element of the array and located between the element and its associated area on the viewing surface for providing controlled illumination of the associated areas including at least a portion of the space surrounding the active element.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.