Coatings produced by thermal spray processes are determined by particle parameters, which can be investigated using various diagnostic systems. With the newly developed PSI (Particle Shape Imaging) four (velocity, size, shape and position) important particle parameters can be measured and evaluated. The data acquisition system consists of two separate optical setups, thus a single particle produces two pictures in the lower and upper area of an ICCD-Camera. These pictures are evaluated by assigning specially developed shape and size parameters to the particles, which in combination with the velocity can be used to predict the coating quality. This instrument can be used to determine the optimum spray parameters (i.e. find the optimal distance between substrate and thermal spray system) and to survey the coating process. A newly developed, mobile PSI-System will allow operation at industrial and research thermal spray facilities.