An optofluidic refractive index sensor based on partial refraction

This article reports on an optofluidic refractive index sensor based on partial refraction. The sample to be measured is injected into a cladding sensing microchannel. The refraction angle and the optical reflectivity change with the variation of the refractive index of the cladding liquid. The refractive index of liquid cladding can be determined by the characterization of the refraction angle and the optical reflectivity. It is demonstrated that the optofluidic refractive index sensor can detect refractive index in the range between 1.37 and 1.45. The sensor has the potential for a seamless integration with lab-on-a-chip devices for concentration and refractive index sensing applications.