Pupil Engineering Method to Enhance the Signal of the Real-time non-invasive Particle Size Distribution Probe in Powders and During Mixing, Drying, Blending, and Milling Processes

A method of monitoring a particle size distribution (PSD) is provided. At least a partially coherent pupil-engineered beam may be produced. A plurality of particles having a particle size distribution (PSD) may be illuminated by the pupil-engineered beam to produce scattered light. The scattered light may be captured by a pixelated photoelectric detector, thereby creating a raw speckled image. An intensity correlation of the raw speckled image may be computed. The intensity correlation may be provided to an inverse module. The inverse module may be configured to determine the PSD based on the intensity correlation. The PSD may be obtained from the inverse module.