Liquid crystal image display system
US4571584A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 22, 1983 |
| Grant date | Feb 18, 1986 |
| Priority date | — |
| Expiry date | Jul 22, 2003 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N3/127
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A liquid crystal display produces a still image derived from a video signal by use of a comparator and selected reference levels to derive the driving signal for the liquid crystal display array. The vertical and horizontal samples and timing pulses derived from the original video signal of the image to be displayed are stored in shift registers, respectively, and then read out into multiplexers for feeding to the liquid crystal display array. The multiplexers are analog gates that have connected thereto in addition to the shift register output signal a plurality of voltages derived from a voltage divider network that sets the level of the voltage applied across each liquid crystal device in the array. No analog-to-digital converter or multiple shift register and specialized switch combination are required and thus the operational margin or sensitivity of the liquid crystal display is not adversely affected and the driving circuit is relatively uncomplicated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.