(680e) Wide Range Particle Sizing for Submicron By Scattering Light Image Analysis

Particle size is one of the important influential factors for product quality such as pharmaceuticals, ceramics, magnets, and other devices using powder, paste or slurry. Monitoring and control of particle size is a great challenge in these products. Particle size monitoring technology, such as Focus Beam Reflectance Measurement (RBRM) and Particle Vision and Measurement (PVM), can measure precise particle size distribution with single particle detection. However, these methods cannot measure submicron and smaller particles. To solve this issue, we developed a new method which could measure submicron particles by analyzing scattering light with microscope. In this method, a size of individual particle is estimated based on small-angle scattering light intensity acquired from microscope image. We studied the limitations of measurable range of particle size for different materials by experiments and simulations using light scattering theory. As a result, this method can measure precise particle size distribution of materials including submicron particles, and the lower limit of measurable particle size is 200 nm in case of alumina and depends on refractive index of the material.