Submersible Interferometric Sensor

This technology reads an interferometer signal using a standard spectrometer. It calculates absolute optical path length difference with very high precision, even when the spectrometer samples are not spaced in the usual “quadrature” way. It has a resolution from 1/1,000 to 1/100,000 of a wavelength, which supports high-precision sensing of parameters like refractive index, which can be used for salinity and density.