A device and method for calibration of pulse oximeters is disclosed. A standard specimen that has optical characteristics of hemoglobin of a known oxygen saturation is placed in the light path of a pulse oximeter probe. The image of a pulse is created by a filter that periodically increases and decreases...http://www.google.de/patents/US4968137?utm_source=gb-gplus-sharePatent US4968137 - Devices and procedures for in vitro testing of pulse oximetry monitors
