A microscope's resolution measures how much detail a user can see. A microscope may have powerful magnifying lenses, but if the resolution is poor, the magnified image is just a blur. Resolution is the shortest distance between two points that a user can still see as separate images under the microscope.
A compound microscope can't distinguish details closer together than 200 nanometers. The most powerful electron microscopes go down as low as .2 nanometers. A microscope loses resolution if the lenses aren't perfectly aligned. Viewing light with shorter wavelengths produces better resolution than longer wavelengths. There are mathematical formulas that use the wavelength and the numerical aperture -- the microscope's ability to gather light -- to calculate resolution. Specimens in which the different parts aren't very distinct may give the user a poorer resolution, even with the best microscopes.
About the Author
A graduate of Oberlin College, Fraser Sherman began writing in 1981. Since then he's researched and written newspaper and magazine stories on city government, court cases, business, real estate and finance, the uses of new technologies and film history. Sherman has worked for more than a decade as a newspaper reporter, and his magazine articles have been published in "Newsweek," "Air & Space," "Backpacker" and "Boys' Life." Sherman is also the author of three film reference books, with a fourth currently under way.
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