Patent ID: 7797983
Filing Date: 2010-09-21
Classification: G01N

Abstract:
1. A system for detecting one or more gases or gas mixtures and/or for measuring the concentration of one or more gases or gas mixtures, said system comprising at least: at least a first light source, a sample space where gas to be detected and/or measured can be arranged, a reference space isolated from the sample space and containing no gas to be detected and/or measured, a measuring chamber, which has a volume V, and to a wall of which at least one aperture is arranged, said at least one aperture being provided with a window for admitting modulated and/or pulsed infrared radiation and/or light into the measuring chamber, and to which measuring chamber gas or gas mixture to be detected and/or measured is arranged, means for conducting a first light beam from the at least first light source into the sample space and further into the measuring chamber, means for conducting a second light beam, in isolation from the sample space, from the first light source or from a second light source into the reference space and further into the measuring chamber, and means for pulsing the first and second light beams, wherein the measuring chamber comprises two chambers in communication with each other by way of an aperture, a first being supplied with said first light beam and a second being supplied with said second light beam, and that the aperture has been arranged to a door arranged to move in response to a pressure difference between the first and second measuring chambers, and that the measuring chamber includes means for measuring the door movement without contact.