Patent · US Expired

Metal halide lamp containing ScI.sub.3 with added cadmium or zinc

US4387319A · kind A · utility

13Cited by
6References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 30, 1981
Grant dateJun 7, 1983
Priority date
Expiry dateMar 30, 2001

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01J61/18
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A high intensity metal halide discharge lamp has a fill comprising mercury, sodium iodide and scandium triiodide plus an inert starting gas. Cadmium or zinc may be added in a molar ratio relative to ScI.sub.3 within the range of 0.04 to 1.0 to achieve a lowering in color temperature of several hundred degrees Kelvin at the cost of a minor decrease in lumens which is offset by an improvement in maintenance.

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