Barium light source method and apparatus
US6433482B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | May 10, 1999 |
| Grant date | Aug 13, 2002 |
| Priority date | — |
| Expiry date | May 10, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J61/18
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Visible light emission is obtained from a plasma containing elemental barium including neutral barium atoms and barium ion species. Neutral barium provides a strong green light emission in the center of the visible spectrum with a highly efficient conversion of electrical energy into visible light. By the selective excitation of barium ionic species, emission of visible light at longer and shorter wavelengths can be obtained simultaneously with the green emission from neutral barium, effectively providing light that is visually perceived as white. A discharge vessel contains the elemental barium and a buffer gas fill therein, and a discharge inducer is utilized to induce a desired discharge temperature and barium vapor pressure therein to produce from the barium vapor a visible light emission. The discharge can be induced utilizing a glow discharge between electrodes in the discharge vessel as well as by inductively or capacitively coupling RF energy into the plasma within the discharge vessel.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.