Electro-photographic printer
US4386836A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 29, 1980 |
| Grant date | Jun 7, 1983 |
| Priority date | — |
| Expiry date | Dec 29, 2000 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02B2075/027
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An electro-photographic printer utilizing a liquid crystal material which operates as a light valve. The liquid crystal material is sandwiched between two base plates which include electrodes which define a plurality of micro-shutters. A light source illuminates one side of the liquid crystal material. A driving circuit selectively applies driving signals to the electrodes for selectively opening and closing the micro-shutters to allow light from the light source to pass therethrough. A photo-sensitive drum on the other side of the liquid crystal receives the light transmitted through the liquid crystal to form characters. The characters are transmitted to a recording paper. The liquid crystal material, which has an inverted dielectric anisotropy on opposite sides of the critical frequency, is selectively driven by selectively applying two different frequency signals to the liquid crystal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.