Phaseless wavelength modulation spectroscopy
US5973782A · kind A · utility
15Cited by
8References
22Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jan 9, 1998 |
| Grant date | Oct 26, 1999 |
| Priority date | — |
| Expiry date | Jan 9, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01J3/4338
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An improvement to wavelength modulation spectroscopy systems operating at frequency .OMEGA. and having a photodetector generating output with frequency components .OMEGA., 2.OMEGA., . . . n.OMEGA., where n is an integer greater than one, the improvement comprising a demodulator operating at frequency .OMEGA.+.delta., where .OMEGA.>>.delta., and additionally recovering signals at n.OMEGA.+n.delta.. The system provides information on multiple detection harmonics simultaneously, no phase adjustment is needed, and the system uses a heterodyne demodulation with its inherent low-noise advantage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.