Polarized light microscopy

Simple techniques include illumination of the sample with polarized light.

Directly transmitted light can, optionally, be blocked with a polariser oriented at 90 degrees to the illumination.

[1] These illumination techniques are most commonly used on birefringent samples where the polarized light interacts strongly with the sample and so generating contrast with the background.

Polarized light microscopy is used extensively in optical mineralogy.

Although the invention of the polarizing microscope is typically attributed to David Brewster around 1815, Brewster clearly acknowledges the priority of Henry Fox Talbot, who published his work in 1834.