Plural-color discharge lamps
US4740729A · kind A · utility
Inventor
Key dates
| Filing date | Apr 13, 1987 |
| Grant date | Apr 26, 1988 |
| Priority date | — |
| Expiry date | Apr 13, 2007 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J61/94
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A discharge lamp has an outer discharge tube and an inner discharge tube. The outer tube includes an envelope of glass enclosing an inert gas, a first electrode mounted within the envelope, a second electrode formed of a transparent film deposited on the exterior surface of the envelope, and a fluorescent material coated on the interior surface of the envelope for producing a light in a desired color when a voltage is applied across the two electrodes. The inner tube is inserted in the outer tube and includes an envelope of glass enclosing an inert gas, a third electrode mounted within the envelope, the third electrode utilizing the second electrode of the outer tube as an opposite electrode for producing luminous discharge, and a fluorescent material coated on the interior surface of the envelope for producing a light in a color different from the one produced by the fluorescent material on the outer tube.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.