DYNAMIC LIGHT SCATTERING MEASURING DEVICE USING PHASE MODULATION TYPE INTERFEROMETRY

摘要

PROBLEM TO BE SOLVED: To provide a dynamic light scattering measuring device using a phase modulation type interferometry capable of clarifying optical path length dependency of a multiple scattering spectrum, and thereby measuring a dynamic characteristic of a medium with excellent accuracy based on scattered light from the high-concentration medium.;SOLUTION: This device is equipped with an optical coupler 5 for dividing light from a low coherence light source 2, a condensing lens 10 for irradiating the sample medium 9 with one light divided by the optical coupler 5, phase modulators 7, 8 for modulating the phase of the other light divided by the optical coupler 5, a spectrum measuring device 12 for measuring the spectrum of interference light between phase-modulated reference light and scattered light emitted from the sample medium 9, and an analysis means for performing dynamic light scattering measurement of particles based on a 1-st order spectrum appearing in an interference light spectrum measured by the spectrum measuring device 12 and corresponding to a fundamental frequency of a phase modulation signal or a higher-order spectrum corresponding to a frequency in double, triple or the like. As for the optical path length s in the sample medium, the quantity s/L standardized by the mean free path of the particles is set to be 3 or less.;COPYRIGHT: (C)2005,JPO&NCIPI