Back to results
US 5,830,132 AGranted
Robust accurate non-invasive analyte monitor
OwnerMark R. Robinsoninventor
Life of this patent
Estimating the term…
Loading patent…
Loading patent…
OwnerMark R. Robinsoninventor
Estimating the term…
An improved method and apparatus for determining noninvasively and in vivo one or more unknown values of a known characteristic, particularly the concentration of an analyte in human tissue. The method includes: (1) irradiating the tissue with infrared energy (400 nm-2400 nm) having at least several wavelengths in a given range of wavelengths so that there is differential absorption of at least some of the wavelengths by the tissue as a function of the wavelengths and the known characteristic, the differential absorption causeing intensity variations of the wavelengths incident from the tissue; (2) providing a first path through the tissue; (3) optimizing the first path for a first sub-region of the range of wavelengths to maximize the differential absorption by at least some of the wavelengths in the first sub-region; (4) providing a second path through the tissue; and (5) optimizing the second path for a second sub-region of the range, to maximize the differential absorption by at least some of the wavelengths in the second sub-region. In the preferred embodiment a third path through the tissue is provided for, which path is optimized for a third sub-region of the range. With this arrangement, spectral variations which are the result of tissue differences (e.g., melanin and temperature) can be reduced. At least one of the paths represents a partial transmission path through the tissue. This partial transmission path may pass through the nail of a finger once and, preferably, twice. Also included are apparatus for: (1) reducing the arterial pulsations within the tissue; and (2) maximizing the blood content i the tissue.
In a method of determining noninvasively and in vivo one or more unknown values of a known characteristic, including the steps of irradiating human tissue with at least one source of infrared energy having at least several wavelengths in a given range of wavelengths so that there is differential absorption of at least some of said wavelengths by said tissue as a function of said wavelengths and said characteristic, said differential absorption causing intensity variations of said wavelengths, collecting with at least one detector at least some of said wavelengths that have traversed through said tissue, and calculating said one or more unknown values of said known characteristic, the improvement comprising:
In a method of determining noninvasively and in vivo one or more unknown values of a known characteristic, including the steps of irradiating human tissue with at least one source of infrared energy having at least several wavelengths in a given range of wavelengths so that there is differential absorption of at least some of said wavelengths by said tissue as a function of said wavelengths and said characteristic, said differential absorption causing intensity variations of said wavelengths, collecting with at least one detector at least some of said wavelengths that have traversed through said tissue, and calculating said one or more unknown values of said known characteristic, the improvement comprising:
Dependencies are inferred from the claim text.