Gaseous species absorption monitor
US5026991A · kind A · utility
50Cited by
7References
24Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Sep 20, 1989 |
| Grant date | Jun 25, 1991 |
| Priority date | — |
| Expiry date | Sep 20, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2021/399
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A wavelength-locked laser gaseous species monitor including a variable wavelength laser with a laser output actively stabilized to a wavelength at or near an absorption wavelength of the species being monitored. The laser is modulated about that wavelength to establish a modulated output with a known frequency and bandwidth. The modulated output is passed through the sample being monitored and then collected. An even harmonic of the collected output with respect to the modulation frequency is determined, and the presence in the sample of the species being monitored is detected from the even harmonic signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.