Patent · US Expired

Electron excited fluorescent display device including screen with rare earth phosphor exhibiting sublinear current density-emission luminance characteristics

US4510414A · kind A · utility

7Cited by
1References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 9, 1983
Grant dateApr 9, 1985
Priority date
Expiry dateMar 9, 2003

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01J29/20
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A rear earth yellow to red emitting phosphor exhibiting the sublinear characteristics when the current density of an excitation electron beam is increased. The phosphor is represented by the general formula: EQU (Ln.sub.1-x-y,Eu.sub.x,Ce.sub.y).sub.2 O.sub.2 S in which Ln is at least one of yttrium, gadolinium, lanthanum and lutetium, x is a number satisfying 10.sup.-4 .ltoreq.x.ltoreq.9.times.10.sup.-2, preferably 10.sup.-2 .ltoreq.x.ltoreq.8.times.10.sup.-2, and y is a number satisfying 10.sup.-6 .ltoreq.y.ltoreq.2.times.10.sup.-3, preferably 2.times.10.sup.-6 .ltoreq.y.ltoreq.10.sup.-3. It exhibits a wide reproduced color range, and free of color drift at a high current. The phosphor is suitable for use in a multi-color cathode ray tube and a multi-color low-velocity electron excited fluorescent display device, and makes it possible to realize a high-performance electronic display unit.

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