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Nova Scotia Museum

Selecting a Child's Microscope

A microscope is a marvellous tool. With it, a tiny insect becomes the most intricate and foreboding of beasts, a moss leaf shows unimagined complexity and table salt reveals its orderly cubic crystals. It can kindle a child's enthusiasm, or create frustration and disillusionment. The difference may lie in your choice of instrument and the way it is used.

Many types of microscopes are manufactured today. Some cost thousands of dollars and have special features to aid the researcher. Others are used for diagnosis in medicine, in quality control for industry and as teaching instruments. The least expensive microscopes are those designed for home use by youngsters. Our purpose is not to compare brand names, but to help you look critically at microscopes and advertisements and make your own comparisons.

A simple magnifying glass can enlarge an image 10 to 15 times at most. A compound microscope is essentially one magnifying lens (the eyepiece) enlarging the image produced by another lens (the objective). Magnification can reach 1200 times. You've likely noticed that the image produced by a magnifying glass is good in the centre but distorted at the edges. Much of the cost of compound microscopes has to do with correcting lenses to eliminate this distortion.

Compound microscopes are used for viewing transparent or very small objects, like individual cells, pond algae or onion skins.

If you prefer to look at larger, thicker objects like rocks, fingers or whole flowers, consider a stereo microscope. Although magnification is lower (10 to 80 times) you can view unprepared specimens in 3D. Stereo microscopes have an eyepiece for each eye. They may be called "geology microscopes".