US 2003/0114737 A1 · Blood component measurement apparatus

Abstract

In a pulse oximeter (blood component measurement apparatus), a subject body is irradiated periodically with red light and infrared light. Then, carried out sequentially in a time sharing manner are the measurement of the transmitted light intensity through the subject body, the measurement of the pulse wave component of the transmitted light intensity, and the measurement of the dark level in the state that the subject body is not irradiated with the light. On the basis of these measurement values, oxygen saturation of the arterial blood is measured. In the present embodiments, each measurement is carried out with a time interval equal to the period corresponding to the line frequency. In this approach, periodic noise of the line frequency or other noise are eliminated in dark level correction. This permits precise measurement of the blood component.

Claims15

Dependent claims

A blood component measurement apparatus for measuring a blood component in the arterial blood of a subject body comprising:

an illuminating device for illuminating said subject body with predetermined light periodically at first timings;
a light intensity detector for detecting light intensity measurement values of light transmitted through said subject body;
a dark level detector for detecting dark level measurement values periodically at second timings without illumination from said illuminating device;
a pulse wave detector for extracting pulse wave component from said light intensity measurement values, and thereby detecting pulse wave measurement values;
and
a blood component measurer for measuring the blood component of said arterial blood on the basis of said light intensity measurement values, said dark level measurement values, and said pulse wave measurement values;
wherein each time interval between said first timings and said second timings corresponds to a line frequency.

4 more elements

Dependencies are inferred from the claim text.

Blood component measurement apparatus

Life of this patent

Blood component measurement apparatus

Life of this patent

Abstract

Claims15