Laserdiffraktiomenetelmä

Laserdiffraktiomenetelmä is a technique used to determine the particle size distribution of a sample. It is based on the principle that when a laser beam encounters particles, it scatters light in different directions. The angle of scattering is inversely proportional to the size of the particles. Larger particles scatter light at smaller angles, while smaller particles scatter light at larger angles.

In the laserdiffraktiomenetelmä, a laser beam is directed through a sample, which can be a suspension or a dry powder. The scattered light is then detected by a series of sensors positioned at various angles. The intensity of the scattered light at each sensor is measured. These intensity measurements are then processed using an algorithm, typically based on Mie theory, to calculate the particle size distribution. The output is usually presented as a histogram or a cumulative distribution curve, showing the proportion of particles within different size ranges.

This method is widely used in various industries, including pharmaceuticals, food and beverage, cement, and materials science, for quality control, process monitoring, and research and development. Its advantages include speed, ease of use, and the ability to analyze a wide range of particle sizes, from sub-micrometers to millimeters. The technique is non-destructive, meaning the sample can often be recovered and used for further analysis. Accurate results depend on factors such as sample preparation, concentration, and the optical properties of the particles.