Patent · US Active

Infrared spectrometer

US7994479B2 · kind B2 · utility

4Cited by
7References
11Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 25, 2008
Grant dateAug 9, 2011
Priority date—
Expiry dateAug 25, 2028

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.