A noninvasive optical oximeter for measuring oxygen saturation of arterial blood. A sample of blood is illuminated with light at two different wavelengths. Light reflected by the blood is sensed by a photodetector and an output signal is created in response thereto. The output signal is processed to form a quotient representing the AC components of the reflected light at each wavelength. The oxygen saturation of the blood is calculated by correlating this quotient with an oxygen saturation reference curve uniquely representative of the blood oxygen saturation characteristics of a particular individual.
Reuben W. Edgar;Dennis W. Gilstad;Ronald L. Branstetter