High-intensity-discharge lamp with improved color rendition of illuminated objects
US4341978A · kind A · utility
2Cited by
6References
3Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jun 12, 1980 |
| Grant date | Jul 27, 1982 |
| Priority date | — |
| Expiry date | Jun 12, 2000 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J61/12
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
High-intensity-discharge lamp is fabricated in a fashion generally similar to a standard high-pressure-mercury lamp which has a red-emitting phosphor coated on the outer envelope. In the present lamp, the discharge-sustaining filling in the arc tube is modified to include a small, predetermined proportion of cadmium which adds radiations of a wavelength of about 490 nm to the composite lamp emission. The resulting composite emission has greatly improved color-rendering properties as compared to a similar lamp which does not incorporate the cadmium addition to the arc tube filling.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.