Low-Cost Optical Flowmeter With Analog Front-End Electronics for Blood Extracorporeal Circulators

The design and realization of a new low-cost instrument for real-time measurement of blood flow particularly developed for extracorporeal blood circulator systems are presented. A self-mixing interferometric technique combined with a dedicated analog signal processing system was adopted to perform an accurate flow measurement. The developed system exhibits an accuracy lower than 3%. The cost of the entire measuring system has been estimated to be about 50 euros.