Light scattering measurement device and light scattering measurement method

A light scattering measurement device of a dispersion liquid including at least one type of particles, the light scattering measurement device comprising:

• a light source unit that irradiates the dispersion liquid with measurement light;
• a parameter setting unit that sets at least one of a scattering angle or a measurement wavelength as a measurement parameter;
• a scattered light measurement unit that obtains a plurality of pieces of scattering intensity data by measuring a scattering intensity of scattered light emitted from the dispersion liquid by the measurement light a plurality of times while changing a value of the measurement parameter set by the parameter setting unit a plurality of times;
• and
• a calculation unit that calculates scattering intensity time variation characteristic data and scattering intensity parameter-dependent data from the plurality of pieces of scattering intensity data obtained by the scattered light measurement unit, fits the calculated scattering intensity time variation characteristic data and the calculated scattering intensity parameter-dependent data using a theoretical formula or a simulation based on a theory of electromagnetic wave behavior that defines a relationship of a refractive index, a particle diameter, and the scattering intensity, specifies a combination of the number of types of particles in the dispersion liquid, a refractive index of a particle, and a particle size distribution of the particle by the fitting based on an evaluation value, and specifies a material of each type of particle of the specified particles in the dispersion liquid, wherein the evaluation value is calculated based on the scattering intensity time variation characteristic data and the scattering intensity parameter-dependent data.