Patent · US Expired

High pressure sodium vapor lamp with high color rendering

US5814944A · kind A · utility

4Cited by
3References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 16, 1997
Grant dateSep 29, 1998
Priority date
Expiry dateJan 16, 2017

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01J61/825
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

High-pressure sodium vapor lamp with high color rendering including, in an arc tube of a light transmitting material formed in a substantially cylindrical shape sealed hermetically at both axial ends, a pair of electrodes disposed internally at both axial ends of the tube and xenon gas of at least 2.5.times.10.sup.4 (Pa) sealed in the tube together with sodium vapor, is so constituted that a lamp voltage upon lighting of the lamp and represented by V (V as a unit), lamp power represented by W (watt), internal diameter of the arc tube represented by .phi. (mm) and distance between the pair of electrodes represented by d (mm) will satisfy the following formulas: EQU 2.0.ltoreq.V/d.ltoreq.2.7 (1) and EQU 20.ltoreq.W/.phi..ltoreq.28 (2)

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