Research Of Laser Particle Sizer Based On Scattering Theory

Particle sizing is more and more important in areas as environment, energy sources and chemistry etc, while nowadays, the laser particle sizer based on scattering theory is widely used in the area of particle sizing, which has advantages as high precision, quick test, good repeatability, wide measuring range, non-touch test, high automatization, simple operation etc. System designing were made out on the hardware and software, and finally achieved and ameliorated the experimental system of laser particle sizer by deeply study of Mie scattering theory and the principle of laser particle sizer. The main contents includes:1,By study of Mie theory, the calculation model of intensity scattered function is set up as well as scattering light intensity distribution by various particles and refractive are obtained through computing.2,Hardware system of laser particle sizer is designed, which include optical system as well as data acquisition and processing circuit, the position of fourier lens and sample pool is changed while designing of optical system. Which reduced the cubage of the whole instrument but not reduce measuring range.3,Annulus parameters of annular detector and position parameter of large angle detectors are calculated strictly by Mie scattering intensity distribution and annular detector is designed and made out independently. Then, the mathematical model of optical system is set up, the basically dominant diagonal light energy distribution matrix obtained can make the result more stable, and serve the inverse processing later.4,Modal algorithm and non-mode algorithm are analysed detailedly, and the non-mode one is picked to mainly study. The combination of optimization algorithm and traditional distribution inverse algorithm is presented, which aims at the shortages that low antinoise ability of non-mode algorithm. The steepest descent inverse algorithm based on P-T theory is fixed which can avoid the huge error may bring by matrix inversion and also enhancing the precision and stability.5,Analysis software and its various functions are achieved to supply a simple and humanness operate panel.6,Abundance of repeated and comparable experiments are done by the experimental system, it indicates, the repeatable error of D5 0 is in 1% as well as good stability while avoid influences of sample dispersing. Finally, factors may bring error to the system are studied, and the precision as well as reliability of the system is improved by solving the main problems.