Hemoglobin oxygen saturation measuring method and the reflected photosensor null which is used for that

摘要

PURPOSE:To prevent the generation of noise by providing light emitting elements and light receiving element for IR light and near IR light to the inside of a small-sized case which is peripherally shielded and is formed transparent only on the top surface as a surface to contact a specimen. CONSTITUTION:A reflected light sensor S is attached with LEDs 2-4 and a photodiode 5 on a substrate 6 in the casing 1 in such a manner that the light emitting surfaces and receiving surface face upward. A transparent epoxy resin 8 is packed into the casing 1. The surface of the top part is polished and the surface thereof is coated with a transparent polyurethane having an excellent antithrombotic characteristic, by which the surface 9 to contact the specimen is formed. The LEDs 2-4 of the sensor S are successively annihilated by driving pulses when blood is dropped onto the surface 9. The intensity of the reflected light of respective wavelengths are measured by the diode 5 when the IR light and near IR light is irradiated. The periphery of the sensor S is shielded with the casing 1 and since the surface 9 is coated with the specimen, the intrusion of the external light is obviated and the generation of the noise is prevented.