Biology 101

Triszan Moore

February 15, 2002

Biology 101

The compound light microscope is used for examining small or thinly sliced sections of objects under magnification that is higher than that of the binocular dissecting light microscope. The term light refers to the method by which light transmits the image to your eye. Compound deals with the microscope having more than one lens. Microscope is the combination of two words. "Micro" meaning small and "scope" meaning view. Microscopes in early times, like Leeuwenhoek's, were called simple because they only had one lens. The compound microscope was created by the Janssens. This creation helped to advance the field of microbiology many years ahead of where it had been only just a few years earlier. The Janssens added a second lens to magnify the image of the primary lens.

The compound light microscope consists of many parts. Parts' enabling the microscope to magnify as high as 400 times an objects normal size. There are two magnification values of interest to the microscopist. They are the optical magnification and the actual magnification. The optical magnification is quite the product of the magnification of the objective lens and the ocular lens. Therefore, if the 45X objective is being used with a 10X ocular, the optical magnification is 450X. This number has little to do with sizes of things but describes the magnification potential of a pair of lenses. A compound light microscope is perhaps the most widely used microscope. Approximately 94% of all students have used a compound light microscope before entering college. The microscope is basically used in high school laboratories.

The compound light microscope is the ideal instrument for observing specimens of small size; be they as tiny as a single celled protozoan, or as large as the beautiful monarch butterfly, the microscope can serve as your window into a whole new world of nature.