Analysis and realization of a fiber-optic turbidity sensor based on measurements of scattered light

We propose a method for sensing the turbidity of a solution by inserting a fiber-optic probe in conjunction with a mirror. The probe consists of seven fibers, which illuminate as well as collect the light scattered from the sample after reflection from the mirror, in order to estimate the turbidity of the sample solution. We have estimated turbidity in terms of total interaction coefficient, a parameter that contains strong signature of the turbidity of a liquid. A light-scattering model based on Monte Carlo simulations is employed to simulate the power collected by the probe, which match reasonably well with the experimental results. The method is simple, and should be useful for detecting suspended impurities in a liquid even in small quantities.