Wavelength specific detection system for measuring the partial pressure of a gas excited by an electron beam
US4692630A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 27, 1986 |
| Grant date | Sep 8, 1987 |
| Priority date | — |
| Expiry date | May 27, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01J3/443
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An optical partial pressure gas analyzer employs an electron beam to excite the outer electrons of gas atoms or molecules, and one or more photomultiplier tubes or other similar detectors to detect wavelengths of photons characteristic of the decay of the outer electrons of one or more species of gas molecules. The photomultiplier tubes have a viewing direction substantially at right angles to the electron beam. A Faraday trap or similar device is employed to avoid secondary electron generation. Thin-film interference filters are favorably employed to pass a specific characteristic wavelength of the desired species, and to reject other wavelengths. An electromechanical filter changer permits each photomultiplier tube to analyze two or more gasses alternately.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.