Instrumental Errors of Optical Particle Counters

抄録

In order to find the instrumental errors, a comparison of nine commercial optical particle counters (OPCs) of five different types was made. Data analyses were performed in the following three steps : (1) The comparison of the same type OPCs showed that counting ratios almost fell within the range from 0.70 to 1.40. These errors are caused not only by the individual difference during manufacture but also by the elapsed time after calibration. (2) The comparison of the different type but the same manufacturer's OPCs suggested that these errors were caused mainly by the differences of the detectable smallest particle size in each channel due to the differences of the optical system. (3) The comparison of the different type and manufacturer's OPCs showed that counting ratios ranged over one order of magnitude, because of the different systems and different calibration methods, and the size distributions obtained from several OPCs were compared with those by different principle instruments.