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:
Dec. 23, 2008
Filed:
Oct. 31, 2007
Martin Lehmann, 1 CH-5610 Wohlen, CH;
Jean-noel Fehr, Palezieux-Village, CH;
Martin Liechti, Bern, CH;
Urban Schnell, INS, CH;
Martin Lehmann, 1 CH-5610 Wohlen, CH;
Jean-Noel Fehr, Palezieux-Village, CH;
Martin Liechti, Bern, CH;
Urban Schnell, INS, CH;
Other;
Abstract
A method of monitoring pressure of a gas species up to at most a predetermined maximum pressure value is disclosed. The method includes exposing the gas species to transmission of laser light, periodically modulating the wavelength of the laser light over a wavelength band including at least one absorption line of the gas species, optoelectrically converting the transmitted laser light, thereby generating an electric output signal, performing at least one of first filtering the electric output signal with a filter characteristic having a lower cut-off frequency not lower than a transition frequency and of second filtering the electric output signal with a bandpass filter characteristic having an upper cut-off frequency not higher than the transition frequency and a lower cut-off frequency above the modulation frequency of the periodic wavelength modulation. The output of at least one of the filterings is evaluated as a pressure indicative signal.