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. 20, 1994
Filed:
Sep. 03, 1992
Richard G Caro, San Francisco, CA (US);
Sirraya, Inc., San Francisco, CA (US);
Abstract
A method and apparatus for determining the presence of an analyte in a medium or the composition of a medium wherein a volume of material is irradiated with temporally-modulated electromagnetic energy at multiple wavelengths. The electromagnetic radiation is detected after it has traversed a portion of the material. Representation signals related to the degree of absorption of electromagnetic energy at various wavelengths in the material and signals related to the path lengths travelled by the electromagnetic radiation in the material are generated, and signals representative of the optical absorption per unit path length at various wavelengths in the medium are derived. The derived wavelength dependence of the optical absorption per unit path length is compared with a calibration model, and the comparison is analyzed to derive concentrations of specific chemical species within the material and the presence of an analyte or composition of the medium. An output indicative of the concentration and composition is then provided.