Electronic displays
US4527863A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 12, 1983 |
| Grant date | Jul 9, 1985 |
| Priority date | — |
| Expiry date | Oct 12, 2003 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G3/001
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A polar co-ordinate display of full 360.degree. arc comprised of electrode bearing substrates each side of a layer of dyed phase change liquid crystal material. One set of electrodes comprises concentric spirals, the other set comprises radials. The display is multiplex addressed using four select waveform signals. These four signals V.sub.1, V.sub.2, V.sub.3, and V.sub.x satisfy the following conditions: EQU RMS(V.sub.x -V.sub.i)=V.sub.p, i=1, 2 or 3; EQU RMS(V.sub.1 -V.sub.2)=V.sub.p ; RMS(V.sub.1 -V.sub.3)=V.sub.0 where V.sub.p is an upper threshold voltage, and V.sub.0 a saturation voltage for dyed phase change hysteresis, and may be of the coded form; PA0 V.sub.1 =,1010,; PA0 V.sub.2 =,1100,; PA0 V.sub.3 =,0101,; PA0 V.sub.x =,0110,. These may be generated using two 2-bit registers with exclusive OR-gate feedback.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.