Polarized light microscopy refers to optical microscopy techniques that use polarized light to ascertain various optical properties of a material. Polarized light microscopes typically consist of a microscope equipped with two polarizers oriented at right angles with respect to each other. The first polarizer is placed in the optical path before the specimen while the second is placed between the sample and the observer or camera. A birefringent specimen (i.e. a specimen with a polarization-dependent refractive index), will fluctuate between light and dark as it is rotated around the optical axis of the microscope. Some optical properties such as pleochromism (different colors when observed at different angles) can be revealed using only one polarization filter.
- Non-destructive technique
- Measure thickness of materials with known birefringence and vice versa.
- Improve contrast of birefringent specimens such as collagen and asbestos fibers.
- Detect birefringence in stressed polymers.