Patent · US Expired

High contrast electroluminescent displays

US4859904A · kind A · utility

6Cited by
3References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 24, 1988
Grant dateAug 22, 1989
Priority date
Expiry dateMay 24, 2008

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH05B33/12
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A d.c. or a.c. electroluminescent panel comprises a transparent substrate, a transparent first electrode film, a thin film phosphor layer, a black or dark powder back layer of electrically conductive material, and a second electrode film. Application of a voltage across the phosphor layer causes it to emit light. In this invention, the black powder back-layer significantly enhances the contrast of the panel.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.