Device, system and method for extracting physiological information

Abstract

The present invention relates to a device, system and a method for extracting physiological information indicative of at least one vital sign of a subject from detected electromagnetic radiation reflected from the subject. The device comprises an input interface for receiving a data stream of detection data derived from detected electromagnetic radiation reflected from a skin region of a subject, wherein the detected electromagnetic radiation is detected by a polarized radiation detector, while the polarization angle of the polarized radiation detector is changed, a PPG extraction unit for extracting a photoplethysmographic, PPG, signal from said detection data, a signal quality determination unit for determining quality metrics from said PPG signal for different settings of the polarization angle of the polarized radiation detector, a selection unit for selecting the optimum quality metric value from the determined quality metrics and for generating polarization control information for use by said polarized radiation detector for setting the polarization angle to an angle value, at which said optimum quality metric value was obtained, for subsequent detection of radiation, and a processor for deriving physiological information indicative of at least one vital sign from the PPG signal.