Patent ID: 6083157
Filing Date: 2000-07-04
Classification: A61B,G01N

Abstract:
A method of determining the concentration of a component from the intensity of electromagnetic waves with at least two selected wavelengths which are reflected by human tissue or transmitted through human tissue, said method comprising the following steps:1.1 converting the intensities of received electromagnetic waves into at least one first and one second electric signal;1.2 forming a continuous first temporal average value of the first signal;1.3 forming a continuous second temporal average value of the second signal;1.4 determining a continuous ratio from said first and second signals as well as from said first and second continuous temporal average values with the exception of regions lying close to the zero passages of alternating components of said first signal and said first average value, and said second signal and said second average value; and1.5 deriving the concentration of the component from said continuous ratio.