Self-mixing laser Doppler: a model for extracorporeal blood flow measurement

A theory is developed to study the spectral characteristics of the signal acquired from self-mixing laser Doppler of extracorporeal blood flow. Doppler shifts is generated by erythrocyte cells interacting with the illumination photons. The resulting signal is mixed in the laser cavity to generate the sensor output. In order to predict analytically the spectrum of the Doppler signal, is assumed:week optical feedback, single scattering event and a Gaussian illumination beam. Predictions are verified by measurements on blood in extracorporeal circulation system.