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:
Mar. 02, 1993
Filed:
Aug. 12, 1991
Takuo Aoyagi, Tokyo, JP;
Nihon Kohden Corporation, Tokyo, JP;
Abstract
An apparatus for measuring the change in the concentration of a pigment in blood is disclosed which comprises: light quantity detecting units for continuously detecting the quantities of radiations of light having different wavelengths that have been transmitted or reflected by living tissue containing pulsating blood; first computing unit which, when the concentration or absorptivity coefficient of a light-absorbing component in the blood changes with respect to light having either one of said wavelengths, computes the quantities of radiations of transmitted or reflected light having the wavelengths when the living tissue is in a state of ischemia on the basis of the constant and pulsating components of the quantity of each radiation of light that has been detected by the light quantity detectors both before and after the change occurred; and second computing unit which continuously determines the concentration of a pigment of interest in the blood by performing calculations based on the results of computation by the first computing means and on the quantities of radiations of light detected by the light quantity detecting units.