Determination of the parameters of suspended particles of arbitrary shape by optoelectronic method

Abstract

Data on the parameters of suspended particles are required in the electronic, optical, chemical and mining industries, powder metallurgy, atmospheric physics, medicine, etc. We present the results of determining the parameters of suspended particles of arbitrary shape using a combined optoelectronic approach, including a photoelectric method and a digital method of image processing. The results of both methods were used to correct the particle parameters and operational control of the laser emitter radiation. The operation of an optoelectronic device used to determine the parameters is based on the analysis of particle images in four projections, as well as on the registration of radiation scattered by particles and collected by an elliptical mirror. Spectrometry of the disperse composition of aerosols was carried out using a photomultiplier tube. The images of suspended particles for digital processing were obtained using a CCD array. It is shown that the applied image processing algorithms make it possible to remove noise, correct a background, improve the boundaries, determine the binarization threshold, exclude small particles, select closed areas and boundaries, split the image into the parts and count the number of particles in each of them, determine the parameters and classify the particles. Moreover, it becomes possible to restore the volumetric shape of a suspended particle and display the main characteristics on a digital indicator with an accuracy of 1%, which is significantly better than that of known similar devices. The results obtained can be used to control air pollution and improve the accuracy of identification of suspended particles of arbitrary shape.