Electrochromic display device having constant color density and driving method therefor
US4479121A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 21, 1981 |
| Grant date | Oct 23, 1984 |
| Priority date | — |
| Expiry date | Apr 21, 2001 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F1/163
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An electrochromic display device has an electrolyte contained between two spaced-apart substrates. A plurality of display segments are disposed on the surface of at least one of the substrates in contact with the electrolyte, and a counter electrode is disposed on the surface of the other substrate in contact with the electrolyte. Each of the display segments comprises a transparent electrode and an electrochromic layer disposed on the transparent electrode such that the display segment exhibits either colored or bleached states depending on the amount of electric charge held by the display segment. A charge transfer voltage is periodically applied between preselected bleached and colored display segments to effect transfer of electric charges through the electrolyte to thereby periodically change the display state. The difference between the coloration electric charge quantity at the present display state and the coloration electric charge quantity at the next display state is compensated for by either injecting or extracting electric charge into or from the display segments so as to maintain the color density constant.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.