A stereo microscope is generally known as a comparison microscope and it is used in scientific fields primarily for comparing two side by side specimens. A stereo microscope is made up of two regular microscopes connected together with an optical bridge. For instance in forensics, it may be necessary to compare to samples to each other, using a traditional microscope the viewer will need to memorize the contents and switch slides, however with the stereo microscope, the viewer can see both slides side by side at the same time.

     

      The stereo microscope was invented in the 1920's primarily for forensic ballistics tests and was used in famous cases resulting in convictions. Today the stereo microscope is for the most part the same; however there are a few important enhancements such as digital imaging, fiber optic illumination, video capabilities and attachments to take photos easily.

     

      A stereo microscope is part of the group of microscopes called optical microscopes. Optical microscopes use refractive lenses to help focus light into the eye. These lenses are usually made from glass; however plastic lenses are also used. Most stereo microscopes can reach a magnification of 1500x, but stereo microscopes are often used for lower power magnifications. In addition, stereo microscopes are primarily used to study larger specimens. Besides using ordinary light to study specimens, ultra violet light can be used to study specimens that are biological in nature, infrared light is also used for thick slices of biological tissue.