Many pharmaceutical and electronics industrial processes have to be carried out in dust free conditions, a particle counter is essential to monitor the amount of airborne particles.
Light is scattered by the particles and detected by a photomultiplier. The amount of light scattered is proportional to the dust concentration.
The size of particles in powders, sprays, and emulsions is important if they are to be manufactured with the required properties.
Scattered laser light is detected by a photomultiplier and the data analysed. The particle size distribution can be calculated from the results.