How to Compare & Contrast a Polarized Microscope & a Light Microscope

Light microscopes diifer from polarized ones in several ways.

Scientists rely on light and polarized microscopes as critical research tools, but there are key differences that determine what each is best suited for. Light microscopes are used in biology, while polarizing microscopes are used in geology.

Light Source

The light source is a major difference between light and polarized microscopes. Both use visible light, usually a halogen lamp, but in a polarized microscope, the light passes through a polarizing filter at its base so that all light rays that enter the microscope move in the same direction. Objects being observed often bend the light rays, and this can be an important clue in identifying unknown objects.

Stage

Every microscope has a stage.

Every microscope has a stage where objects being identified are placed. A light microscope has a fixed stage, but a polarized microscope has a rotating stage. When the stage rotates, so does the object on it; some objects will bend polarized light rays differently as their orientation changes.

Analyzer

Polarized microscopes have a filter called an analyzer, a polarized film oriented perpendicular to the polarizer at the base of the microscope that is inserted between an object and the eyepiece. Only rays bent by the object make it through the analyzer to the eyepiece.

References

• Optical Microscopy and Specimen Preparation
• Basic Concepts in Optical Microscopy
• Introduction to Polarized Light Microscopy