不同光源对激光尘埃粒子计数器性能的影响

使用Beam Profile2350光束诊断仪测量了氦氖激光和半导体激光两种典型光源的光束特性，并分析了将它们作为激光尘埃粒子计数器的光源时，其在光敏区所产生光场的不均匀性。同时讨论了光场不均匀对计数器性能的影响，计算了两种不同光源下，计数器计数效率和分辨比率的差异。结果表明，以半导体激光作为计数器光源时，光敏区的光强均匀性更好，计数效率更高，粒径的分辨比率较氦氖激光作用时提高了17％，增大了粒径的有效测量范围。

Research on performances of LPCS with different lamphouses

Light intensity distributions of two typical lamp-houses used in Laser Particle Counter System (LPCS)——He-Ne laser and semiconductor laser are measured by Beam Pro_(file)2350. According to the results, intensity uniformity of sensitive volumes formed by two lamp-houses respectively is analyzed. Using the LPCS, the particle size distributions of the normal particles are measured and corresponding counting efficiency and distinguishability are calculated. The results indicate that intensity uniformity of sensitive volume formed by semiconductor laser is better than that formed by He-Ne laser, and correspondingly, the former has better counting efficiency and distinguishability. By comparision with using He-Ne laser, LPCS using semiconductor laser can make its distinguishability of particle diameters increase 17%.