The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 20, 2007
Filed:
Jul. 30, 2004
Bert Willing, Blonay, CH;
Markus Kohli, Grandson, CH;
Andreas Seifert, Denens, CH;
IR Microsystems AG, Lausanne, CH;
Abstract
A gas detector device comprises at least a VCSEL source () and at least a light sensor () for detecting a light beam () having passed through a sample chamber () containing a given gas to be detected. The sensor is a photodiode in a first embodiment and its detection signal is time derivated by an electronic derivator () and then provided to two lock-in amplifiers () in order to generate a F-detection and a 2F-detection, F being the frequency of a wavelength modulation of the source, and thus to provide two corresponding measuring signals the division of which gives a precise value of the gas concentration. In a second embodiment, the source is a pyroelectric sensor which directly provides a detection signal proportional to the time derivate of the light beam incident on this sensor. In this last case, the electronic derivator is thus eliminated.