Apparatus for determining the concentration of light-absorbing materials in blood.

摘要

Light beams of different wavelengths, emitted from a light generating means (1,2,3) are transmitted through a living tissue. The transmitted light beams are converted into electrical signals by a photoelectric transducing means (6). A pulsation calculating means calculates a pulsation of an absorbance of tissue of a living tissue for each wavelength on the basis of the output signal of the photoelectric transducing means (6). By using this, a pulsation ratio calculating means (15) calculates the ratio of the pulsations of the absorbance values. A concentration calculating means puts the output signal of the pulsation ratio calculating means (15) into a formula having a single unknown on the tissue term, which is constructed on the basis of the fact that a predetermined relation is present between the tissue terms of the respective wavelengths, thereby calculating a value of the tissue term and the concentration of light absorbing material in blood. <IMAGE>