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Cite or link this publication as: doi:doi:10.1117/12.874170
Pulse oximeters measure a patients heart rate and blood oxygenationby illuminating the skin and measuring the intensity of the light that has propagated through it. The measured intensities, called photoplethysmograms (PPGs), are highly susceptible to motion, which candistort the PPG derived data. Part of the motion artifacts are considered to result from sensor deformation, leading to a change in emitter-detector distance. It is hypothesized that these motion artifacts correlate to movement of the emitter with respect to the skin. This has been investigated in a laboratory setup in which motion artifacts can be reproducibly generated by translating the emitter with respect to a flowcell that models skin perfusion. The top of the flowcell is a diffuse scattering Delrin skin phantom under which a cardiac induced blood pulse is modeled by a changing milk volume. By illuminating the flowcell, a PPG can be measured. The emitters translation has been accurately measured using self-mixing interferometry (SMI). The motion artifacts in the PPG as a result of emitter motion are shown to correlate with the emitters displacement. Moreover, it is shown that these artifacts are significantly reduced by a least-mean-square algorithm that uses the emitters displacement measured via SMI as artifact reference.