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:
Sep. 08, 2009
Filed:
Sep. 07, 2005
Paul Wilkins, Vantaa, FI;
Samuli Laukkanen, Rajamäki, FI;
Paul Wilkins, Vantaa, FI;
Samuli Laukkanen, Rajamäki, FI;
Vaisala Oyj, Helsinki, FI;
Abstract
A method for improving optical measurement of gas concentration includes steps for directing narrow band light to the gas to be measured and measuring the attenuation of the light in the gas, modulating the center wavelength of the light source around or over a first predetermined absorption maximum (absorption line) of the measured gas and aside of it, measuring the attenuation of the light in the gas as a function of the center wavelength of the light, and determining the gas concentration based on the measurement. The center wavelength of the light is varied such that the center wavelength is adapted to coincide with at least one other absorption maximum (peak) with different absorption properties of the gas to be measured, and correspondingly the attenuation of the other absorption maximum or maxima is measured as a function of the center wavelength of the light.