Commonly Used Terms

Magnification: The degree to which the specimen (viewed object) is enlarged. This is normally expressed by a number followed by an "X" which signifies power. To determine the magnifying power based on the lens diopter use the formula below.

        

Diopter: Identifies the refractive (light bending) capacity of a lens. Note: the rated magnifying power of a lens is based on the specimen being viewed at the full focal length.

Helpful Hints

As a magnifying power increases, the focal length and field of view decrease in size (see chart of focal length).

Eyes should be 8-10 inches above when viewing comfort and proper ergonomic position to avoid neck and shoulder muscle fatigue.

Generally, 5-diopter is the maximum diopter that can be used for assembly work (with an 8 inch focal length for most tools to fit under for work, such lenses are for inspection purposes only).