Incandescent lamp filament with surface crystallites and method of formation
US5389853A · kind A · utility
6Cited by
10References
15Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Oct 1, 1992 |
| Grant date | Feb 14, 1995 |
| Priority date | — |
| Expiry date | Oct 1, 2012 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01K3/02
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The invention refers to a filament having improved emission of visible light. The emissivity of a tungsten filament is improved by depositing a layer of submicron-to-micron crystallites on the filament, the layer having substantially submicron spacing between crystallites. The crystallites being formed from tungsten or a tungsten alloy of up to 1 weight percent thorium, up to 10 weight percent of at least one of rhenium, tantalum, or niobium, and the balance substantially tungsten.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.