A Particle Detection Device Based on Multi-angle Laser Scattering

A particle detection device based on multi-angle laser scattering is designed to address the shortcomings of the current single-angle light scattering particle detection device. This device utilizes a 650 nm laser as the incident light source and four photodiodes (PDs) located at different light extraction angles to receive the scattered light from the particles in the detection area. The particle size distribution and mass concentration of the particles in the air stream are detected and the final results are transmitted through a serial port using laser stabilization circuits, photoelectric conversion circuits, signal processing circuits, and communication circuits. The experimental results indicate that the multi-angle laser scattering-based particle detection device is 5.14% and 7.51% more counting efficient than the single-angle scattering particle detection device in the particle size range of 2.5μm∼5μm and 5μm∼10μm, respectively. The device is in fine agreement with Lube's PC-3A in terms of mass concentration detection results, with the maximum error within 7.8% at the same time. Linear fitting of the resulting mass concentration output by the two devices shows that the linear correlation coefficient of the two sets of data reaches 0.9559, and the data correlation is high. The device's detection performance in a wide range of particle sizes can meet the detection needs of common atmospheric particles.