基于光散射的粒子计数器研究OACHSSCD

Aims:This paper aims to develop a particle counting system for measuring the number concentration of micron-scale particles and complete its system verification.Methods:Based on the principle of Mie scattering,the scattered light intensity and frequency of laser on the paticles were measured by a photodiode,and then converted into the particle size and quantity by a signal processing system.Combined with a right-angle optical path,a triple stray light suppression design,and a low-noise amplification and filtering circuit,the system noise was reduced synergistically.Results:The test results showed that the system noise standard deviation was reduced from 9.84 mV to 4.73 mV;and the peak noise voltage was reduced by 51.9％,which effectively improved the signal-to-noise ratio(SNR)of the scattered light signal and achieved accurate capture and stable detection of the scattered light signal from micron-scale particles.Conclusions:The developed particle counting system provides an effective technical means for the accurate measurement and performance evaluation of micron-scale particles.