Light-scattering instrumentation that process

A photometer is any instrument that measures the intensity of light. A spectrometer is any instrument that separates light or mass into its component parts by a scattering process... 

Particle size and distributions can be determined by a number of different methods. The technique described here is light scattering. Different measurement methods produce different results which can be correlated experimentally. The absence of distribution standards for light scattering particle sizing instruments precludes any determination of size accuracy. This is further complicated by particles of non-spherical shape which makes the concept of size very difficult to define. However, for particulate materials encountered in most industrial processes, the assumption that particles are spheres produces quite useful results that are repeatable and relate to important parameters of many processes. 

Insitec now forms part of Malvern Instruments but is still based in California for process and laboratory R D. The EPCS are laser-based instruments for in-line particle measurements that provide information on particle volume concentration and size distribution. EPCS instruments are part of the larger group of electro-optical instruments (MALLS) whose principle of operation is based on light scattering from a group (or ensemble) of particles. Unlike other instruments operating on this principle, the EPCS can perform direct measurements of particle laden flow stream provided the concentration is within operating limits. 

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