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. 07, 1993
Filed:
Jan. 10, 1991
Steven M Maggard, Barboursville, WV (US);
Ashland Oil, Inc., Ashland, KY (US);
Abstract
A calibrated spectrometer can indirectly determine a physical or chemical property of a sample based upon spectral responses measured by the spectrometer with respect to the particular sample. This invention is directed to a method for calibrating or recalibrating a first spectrometer in light of a second spectrometer, or itself, respectively. The calibration employs a unique selection and manipulation of spectral data obtained from both the first and the second instrument. The recalibration employs a unique selection and manipulation of spectral data from the same first instrument, that is obtained both before and after the need for recalibration arises. Instead of modifying the respective responses of the first and second instrument, or the first instrument before and after the need for calibration arises, this invention modifies the calibration equation of the second, or recalibrated instrument, to yield consistent results to those obtained by the first instrument, or the first instrument before it goes out of calibration. A calibration equation is an equation which transforms spectral data of a particular sample at a variety of wavelengths to a calculated value for a chemical or physical property. Generally, the form of such calibration equations is that of a linear combination of absorbances or mathematical transforms of absorbances measured by the first and second instrument for each sample. The accuracy of the calibrated or recalibrated instrument is maintained and in some instances improved.