PURPOSE: To make unnecessary the electric supply to a sensor and to prevent an electric shock, by sending light to a light absorbing body altering an absorption spectrum of transmitted light by reacting to oxygen reversibly, and detecting passed light.
CONSTITUTION: A light absorbing body 11 such as N-N'-dimethylaniline is put in a cell 12 and a membrane 13 passing through oxygen but not permeating light absorbing body liquids is provded on the lower surface of the cell 12. A holder 10 of the cell 12 is brought into contact with the skin and infrared rays are irradiated through infrared-ray-irradiating parts 17aW17c to heat the circumference of measuring surface. Discharge of oxygen diffused through the tissue of the body and discharged from the skin, is accelerated by this heating and oxygen is caught by the body 11 through the membrane 13. Then, a complex is formed by reacting oxygen to the body 11 reversibly and color is changed in accordance with the quantity. Here, light is sent to the body 11 through a light sending passage 14a and passed light is sent to a spectroscope through a photodetection pasage 15a and the reacted quantity of oxygen is found from the variation of an absorption spectrum. Hereby, partial pressure of oxygen in the artery is known safely.
ONO KOUZOU
HIRAMOTO JIYUNICHI
