Monitoring device and method for compensating nonlinear effects in vital sign monitoring

摘要

The present invention relates to a monitoring device 10, comprising a light source 14 emitting light to a body part 12 of a living body, a measuring light element resulting from the interaction of the ambient light element 30 and the body part 12 of the emitted light A photosensor 18 receiving light 16 including 32 and generating an output signal 34, the transfer function representing a relationship between the output signal 34 and the received light; An ambient light cancellation unit 20 for separating said output signal 34 into a first signal portion 36 corresponding to 30 and a second signal portion 38 corresponding to said measurement light element 32; And an ambient light modulation removal unit 22 for compensating for variations in the ambient light element 30 by demodulating the second signal portion 38 based on the transfer function f and the first signal portion 36.