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:
Jun. 29, 1993
Filed:
Aug. 14, 1992
Richard H Clarke, Big Sky, MT (US);
Qian Wang, Boston, MA (US);
Angiomedics II, Inc., Newton, MA (US);
Abstract
Systems and methods for non-invasive blood analysis are disclosed in which blood is illuminated at a plurality of discrete wavelengths selected from the near infrared spectrum. Measurements of the intensity of transmitted or reflected light at such wavelengths are taken, and an analysis of transmittance or reflectance ratios for various wavelengths is performed. Changes in the ratios can be correlated with specific near infrared (IR) absorption peak for the analyte which varies with concentration of the analyte (the data wavelength) and the a second (reference) wavelength being sufficiently removed from the first so that measurements of light absorption at this second wavelength are relatively insensitive to the concentration of the analyte and yet the second wavelength is sufficiently close to the first wavelength to minimize interference from scattering effects and the like. Typically, the window bracketing these closely spaced wavelengths will be less than about 300 nm and preferably less than about 60 nm wide and, in some instances, more preferably less than about 30 nm wide.