Patent · US Expired

Method for determining the concentration of a specific gas and an analyzer

US5739910A · kind A · utility

4Cited by
4References
13Claims
0Family size

Assignee

Inventor

Key dates

Filing dateNov 26, 1996
Grant dateApr 14, 1998
Priority date
Expiry dateNov 26, 2016

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01N2021/8585
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A method and an analyzer for determining the concentration of and/or identifying a specific gas are described. The analyzer has a test chamber through which a gas sample is carried. The gas sample then passes across a first substrate on which a first coating and a second coating are arranged. The second coating is made of a substance which selectively absorbs a specific gas, or a specific group of gases. A light source directs a light beam with a pre-defined polarization at the substrate and coatings. Polarization of the ensuring reflected light beam changes due to reflection in and interaction with the coatings. This change is determined by a calculation unit by determining the reflected light beam's polarization in a photodetector. Adsorption causes polarization changes which are only related to the concentration of the specific gas which can accordingly be identified.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.