Polarised light microscope

The polarised light microscope is a light microscope used principally to examine minerals.

Polarised light microscope technique

The polarised light microscope is a light microscope which uses a polarised light beam (waves vibrating in a single plane). To polarise the light, a polariser is positioned after the light source in front of the sample. The second polariser called the analyser is placed perpendicularly to the first and does not therefore allow the light which has already been polarised to pass through.

However, when a sample placed between the two polarisers interferes with the light beam it then acquires new vibrations, some of which pass through the analyser.

Depending on the features of the light received, the composition of the sample being examined can be established.

Use of the polarised light microscope

The polarised light microscope allows rock minerals to be examined and identified. The mineral is prepared by preparing a fine section and polishing it to a thickness of approximately 30 micrometers.