Non-uniform resistance cathode beam mode fluorescent lamp
US4413204A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 4, 1982 |
| Grant date | Nov 1, 1983 |
| Priority date | — |
| Expiry date | Jan 4, 2002 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J61/72
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The lamp shown herein is a beam mode fluorescent lamp for general lighting applications. The lamp comprises a light transmitting envelope, having a phosphor coating on its inner surface, enclosing a thermionic cathode for emitting electrons and an anode for accelerating the electrons and forming an electron beam, and a fill material, such as mercury, which emits ultraviolet radiation upon excitation. The cathode configuration provides for the elimination of "hot spots" due to ion bombardment at the low potential end of the cathode and for higher overall cathode emission of electrons. Various methods are employed to accomplish these ends, such as: segmenting the cathode, pitch variation of the cathode winding; ion probes and a non-uniform primary coil wound around a larger mandrel wire.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.