The weighting of fractions retained in a series of sieves is a reference method that has been used for decades and is duly normalized. Image analysis techniques, only when properly implemented, predict the result of sieving with perfect correlation.
A 6-gram sand sample distributed by the European Bureau for Certified Reference Material, under reference BCR 68, has been analyzed with the Occhio Zephyr ESR. Relative weight fractions have been computed and results are compared to mean and standard deviation data obtained from sieving by five European reference labs. Zephyr ESR achieves perfect results with only a fraction of the material and within a fraction of the time required...to clean the sieves!
Advantages of optical over mechanical sieving:
• Accurate and real time analysis of individual particles
• Capability of measuring very limited material quantities
• Capability of working with very lightweight and friable material
• Automatically generated report of results
• Normalized or user-defined mesh intervals
• No clogging, no wear
• Simultaneous size and shape analysis