Optogalvanic spectroscopy with phase independent detection
US5706082A · kind A · utility
8Cited by
2References
17Claims
0Family size
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Key dates
| Filing date | Mar 12, 1997 |
| Grant date | Jan 6, 1998 |
| Priority date | — |
| Expiry date | Mar 12, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N27/628
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
In an optogalvanic spectroscopy system, a plasma is exposed to light at a wavelength associated with a particular species in the analyte. The light is amplitude modulated. The amplitude of a modulated component in the signal representing electrical impedance of the plasma is detected in a phase independent manner, so that the detected amplitude is substantially independent of the phase of the modulated component in the impedance signal relative to the amplitude modulation of the light. The system has reduced sensitivity to changes in the spectrum of the applied light.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.