Patent · US Expired

Electric discharge devices

USRE30831E · kind E · reissue

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1References
9Claims
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Assignee

Inventors

Key dates

Filing dateDec 1, 1978
Grant dateDec 22, 1981
Priority date
Expiry dateDec 1, 1998

Classification

  • Technology area (CPC —)General

Abstract

The inclusion of an alkali metal halide in the gas fill of a high pressure mercury and aluminium halide discharge lamp improves the color appearance of the lamp; notably by lowering the color temperature, while maintaining or even increasing the efficacy and stability of the discharge. Preferred contents are 10 to 30 mg cm.sup.-3 mercury, 5 to 100 .mu.mol cm.sup.-3 aluminium halide and 0.5 to 150 .mu.mol cm.sup.3 alkali metal halide, with the molar ratio of alkali metal halide to aluminium halide in the range 0.1 to 1.5 and the total number of aluminium and alkali metal atoms preferably greater than the total number of halogen atoms.

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