Measuring principle: Scattered light analysis according to Mie theory in accordance with DIN/ISO 13320
Measuring range: 0.01 µm - 3000 µm
Type of analysis: Wet measurement

A sample that passes through a focussed beam of light scatters the light at an angle and intensity that depends on the particle size:

• smaller particles scatter the light at wide angles with lower intensity
• larger particles scatter the light at narrower angles with greater intensity

Measuring the intensity of the diffracted light as a function of the angle, followed by processing this data using a mathematical model, makes it possible to calculate the particle size distribution of the sample.

The device is used in the working group „Coastal Anthropocene” to determine the particle size distribution in sediments and soil samples. If necessary, pre-treatment with hydrochloric acid (destruction of carbonates) and/or hydrogen peroxide (oxidation of organic components) must be carried out. In order to completely disperse a clay content of the sample, the clay minerals should be coated with lyophilic cations (overhead shaking with Na polyphosphate).