Patent ID: 8050730

Claim:
A method for eliminating interference in oxygen content measurement, comprising: collecting a first wavelength light and a second wavelength light transmitting through an object to be measured, and converting collected signals into electric signals to form a plethysmogram; normalizing the plethysmogram and decomposing the normalized plethysmogram into a combination of an ideal plethysmogram and a noise component and to expand the ideal plethysmogram by using functions that make up an orthonormal system; eliminating the noise component in the plethysmogram by performing at least one differentiation operation upon the plethysmogram, in which the noise component comprises a first noise component caused by motion or movement of the object during the oxygen content measurement, and a constant corresponding to the first noise component is generated by performing the at least one differentiation operation; and restoring the plethysmogram without the noise component through an integration operation.