Thermal electron source
US4733086A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 7, 1986 |
| Grant date | Mar 22, 1988 |
| Priority date | — |
| Expiry date | Mar 7, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N27/64
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A thermal electron source suitable for use in an electron capture detector comprises a source of stable ultra-violet light, an ultra-violet transparent support member (20,31) located in the path of the ultra-violet light (41) and a thin photo-emissive metallic layer (1A, 24, 33) coated over the surface of the support member remote from the source. In one form the source is a cylindrical mercury vapor lamp (1) with the photo-emissive layer coated directly on the lamp. The coated lamp may then be enclosed within a cylindrical anode (8) with a gas flow between them and the electrical current is measured between the anode and cathode. In an alternative arrangement a planar geometrical assembly is provided. Preferably the photo-emissive material is gold and the carrier gas is an argon-methane mixture.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.