General Electric Company

Robert L Bateman, Jr

Gary Robert Allen

Thomas G Parham

Paul G Mathews

John M Davenport

Curtis E Scott

Cynthia A Secen

Fused quartz containing europium oxide, titanium dioxide and cerium oxide has been found to be effective for absorbing UV radiation while transmitting visible light radiation. Uses for this material include lamp envelopes and shrouds for halogen-incandescent lamps and metal halide arc discharge lamps which emit both UV and visible light radiation.

UV absorbing fused quartz and its use for lamp envelopes

The subject invention, therefore, relates to a multi-layer coating for use on a thick-walled metal halide lamp which emits visible light radiation and absorbs and reflects UV radiation, and which further manages the thermal non-uniformity problems across the thickness of the arc tube to substantially eliminate devitrification problems.

UV Radiation-absorbing coatings and their use in lamps

Fused quartz containing both titanium dioxide and cerium oxide as UV absorbing dopants has been found to be particularly effective for lamp envelopes for high temperature lamps such as halogen-incandescent lamps and metal halide arc discharge lamps which emit both UV and visible light radiation. The codoped quartz transmits visible radiation and absorbs a substantial portion of the emitted UV radiation. The UV absorption is far superior at temperatures above 500.degree. C. and the codoped quartz does not react with the fill within.

Growing community of inventors

Southern Shores, NC, United States of America

Robert L Bateman, Jr