The project aims to develop a proof of concept pre-prototype capable of delivering results with comparable or superior accuracy to those obtained by plasmonic techniques using differential self-mixing interferometry techniques (DSMI) as the basis technology, and to explore options for its exploitation using the preprototype as demonstrator. 

DSMI is a method developed and patented at CD6 from UPC, which can measure changes in the optical path with a resolution of just a few nanometers. Potentially, therefore, overcomes the resolution and cost of plasmonic sensors while it measures the same parameter. The technique is based on classical self-mixing interferometry (SMI), where the effect of interference occurs inside the cavity of a laser diode as a result of the backscatter of the beam of a partially reflective target. This interference modulates the power emitted by the laser. It is possible to process this power modulation ot extract data on the changes in the optical path covered. This is an extremely economical method, self-aligned, compact and robust, which works just pointing the laser diode to the region to be measured. The method has been already used to measure various biological and physical constants.