Gas discharge lamp envelope comprising a barium sulphate protective layer disposed on its inner surface
Number of patents in Portfolio can not be more than 2000
United States of America Patent
Stats
-
Apr 10, 1990
Grant Date -
N/A
app pub date -
Apr 13, 1988
filing date -
Apr 27, 1987
priority date (Note) -
Expired
status (Latency Note)
Importance
Abstract
A protective layer of BaSO.sub.4 or BaSO.sub.4 mixed with SiO.sub.2 is applied in suspension to the inner surface of the glass discharge tube or envelope of a gas discharge lamp of the metal vapour type. The protective layer prevents contact, e.g., of mercury in the discharge chamber with amalgam-forming substances present in the glass surface of the lamp discharge tube. In addition, the crystals of the protective layer re-reflect shortwave ultraviolet radiation back to the layer of luminescent substance, thereby to generate visible light and increasing the efficiency of the lamp. The protective layer results in a marked decrease in the prior art's accepted reduction in the lamp luminance in relation to lamp burning time.
First Claim
Family
International Classification(s)
Cited Art Landscape
Patent Citation Ranking
Advertisement
Advertisement
Advertisement
Recipient Email Address
Recipient Email Address
Comment
Recipient Email Address
Add to Portfolio(s)
To add this patent to one, or more, of your portfolios, simply click the add button.
This Patent is in these Portfolios:
Add to additional portfolios:
Last Refreshed On:
Changes done successfully