Fig. 1. Measuring system of particle counter

Fig. 2. Structure diagram of light cavity. (a) Structural design diagram; (b) structural simulation diagram

Fig. 3. Illuminance distribution maps of photosurface of detector at different distances from concave reflector. (a) 12.5 mm;(b) 13.0 mm; (c) 14.5 mm; (d) 15.0 mm

Fig. 4. Structure diagram of sensor's pneumatic loop

Fig. 5. Structure diagrams of gas jet. (a) General jet; (b) sheath flow jet

Fig. 6. TSP concentrations of prototype and TSI 8533

Fig. 7. TSP concentrations of prototype and TSI 8533 after inversion parameters optimized

Fig. 8. Performance test results of the two kinds of jets

Fig. 9. Influence of gas flow rate on the measurement of PM_2.5, PM₁₀ and TSP concentration. (a) PM_2.5; (b) PM₁₀; (c) TSP

Fig. 10. PM_2.5, PM₁₀ and TSP concentration measurement of prototype and TSI 8533 at different concentrations. (a) PM_2.5; (b) PM₁₀; (c) TSP