Liquid crystal cell for image projections and method of operating same
US4799770A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 8, 1988 |
| Grant date | Jan 24, 1989 |
| Priority date | — |
| Expiry date | Mar 8, 2008 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S359/90
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A liquid crystal cell for an image projection apparatus has a liquid crystal layer sandwiched between two conductive layers. The layer surface is divided into one or more regions and one of the sandwiching conductive layers is divided into separate sections each matching a different region. Busbars are bonded on the other of these conductive layers along the edges and boundary lines between adjacent regions (resistors) such that negative and positive writing/erasing can be performed in selected region or regions. By applying one or more current pulses in one or more of these resistors, the corresponding region or regions can be more completely erased and a uniform dark background can be created therein.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.