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:
Jul. 18, 2000
Filed:
May. 21, 1998
Stephen D Walker, Boulder, CO (US);
Robert A Nichols, Thornton, CO (US);
William A Curnan, Boulder, CO (US);
Sophat Svai, Thornton, CO (US);
James R Braig, Piedmont, CA (US);
Daniel S Goldberger, Boulder, CO (US);
Square One Technology, Inc., Boulder, CO (US);
Abstract
A system and method for determining the concentration of an analyte such as oxygen in an unknown gas sample. A Vertical Cavity Surface Emitting Laser (VCSEL) is used as a variable wavelength light source which is 'swept' through a wavelength range by varying the drive signal applied thereto. Quantitative spectroscopic analysis of the unknown gas sample is performed without the requirement of feedback circuitry for tuning the light source to the characteristic frequency of an analyte. Instead, the VCSEL is repeatedly 'swept' through a range of frequencies determined by the drive signal, and the absorption is measured by the detector. The absorption lines do not always occur at the same place but instead move along around during the sweep based on the temperature and baseline current. The absorption at a particular wavelength may be determined by overlaying the drive signal and its timing information over the detected absorption signal.