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:
Nov. 12, 2002
Filed:
Mar. 26, 2001
Robert T. Stone, Sunnyvale, CA (US);
Other;
Abstract
A method for determining the blood constituents of a patient comprising coupling an oximeter sensor arrangement to a tissue region of the patient; passing first and second lights through the patient's tissue region for a first period of time while the venous blood in the tissue region has a first volume and for a second period of time while the venous blood in the tissue region has a second volume, the first light being substantially in a red light range and the second light being substantially in an infrared light range; detecting a red light signal and an infrared light signal, the red and infrared signals having at least first and second frequencies; computing a first ratio of the red and infrared signals at the first frequency; computing a second ratio of the red and infrared signals at the second frequency; comparing the first and second ratios to determine a first blood constituent.