Infrared spectrometer
US7427760B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Nov 30, 2006 |
| Grant date | Sep 23, 2008 |
| Priority date | — |
| Expiry date | Nov 30, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2021/399
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Method and apparatus for detecting, by absorption spectroscopy, an isotopic ratio of a sample, by passing first and second laser beams of different frequencies through the sample. Two IR absorption cells are used, a first containing a reference gas of known isotopic ratio and the second containing a sample of unknown isotopic ratio. An interlacer or reflective chopper may be used so that as the laser frequencies are scanned the absorption of the sample cell and the reference cell are detected alternately. This ensures that the apparatus is continuously calibrated and rejects the baseline noise when phase sensitive detection is used.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.