Characterization of individual cotton fibers via light-scattering experiments

A detailed experimental/theoretical study is conducted to explore the fundamental nature of individual cotton fibers via light-scattering experiments. For this purpose, a new precision nephelometer is built and calibrated with quartz fibers. In the experiments, iris opening (viewing angle) and scanning range and rate were determined to be the key parameters for precision measurements. The experimental results are compared against the theoretical predictions based on a finite element model. It is shown that the scattered intensity profiles as a function of scattering angle (θ) can be related to the quality (fineness) of cotton. At small scattering angles of θ < 10 deg, these profiles can be used to infer the shape (cross section) of cotton fibers. On the other hand, within the range of 30 deg < θ < 50 deg they may be used to evaluate single-fiber cotton quality (fineness).