Automatic Calculation of Refractive Index in Laser Diffraction Particle Size Distribution Analyzer

Introduction

When using a particle size distribution analyzer based on the laser diffraction and scattering principle, selecting the proper refractive index can be difficult, but it is very important. Various methods that require experience and / or theoretical knowledge have been proposed for addressing this issue. Whichever the approach, however, some manual operation must be performed by the operator, which in turn requires that the operator have an understanding of the measurement principles as well as some degree of experience. Performing this operation has never been very easy. The WingSALDII software, provided with the Shimadzu Laser Diffraction Particle Size Analyzer, includes a Refractive Index Automatic Calculation feature that was not available in previous versions of the software. Utilizing this feature, the software automatically calculates refractive indices that are appropriate for the measured sample, listing the top 5 candidates. The calculation process is based on the concept of the LDR (Light Intensity Distribution Reproduction) method. In this report, we introduce the refractive index automatic calculation feature using the measurement results obtained for actual samples.

November 28, 2011 GMT