Sensitivity-enhanced optical sensor based on multilayer coated Fabry-Perot interferometer

A high-sensitivity optical sensor based on a Fabry-Perot interferometer (FPI) has been demonstrated. The cavity of the FPI is formed by two parallel half-reflective film-coated glass substrates with a distance of 1 mm and works as the sensing area. The interaction between the propagating wave and the analyte gives the sensing signal. High sensitivity of 1149 nm/RIU has been achieved for the wavelength interrogation. The Fabry-Perot sensor can be made into a large array with multiple microfluidic channels to detect the different types of analytes. It has great potential in biochemical sensing. (C) 2022 Society of Photo-Optical Instrumentation Engineers (SPIE)