Light Microscopes

the basic theory of the light microscope A microscopelink to an Internet Website is an instrument that produces an enlarged image of an object. Biologists use microscopes to study things that are too small to be seen with the unaided eye. Most microscopes are called light microscopes because they accomplish their task by using lenses to bend light rays.

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Observing an object:

Magnification: the increase of an object's apparent size.

Resolution: the power to show details clearly. Resolution allows the viewer to see two objects that are very close together as two objects rather than as one.

Compound microscopes use multiple lenses to produce an increase in magnification. If the eyepiece lens enlarges by a factor of 10 (10X) and the objective lens enlarges by a factor of 40 (40X), the total magnification is the product of the two - 400X. Resolution is controlled by the quality of the lenses being used - the better the lenses, the better the resoultion.

Basic parts of a compound light microscope:

Care and handling:

A microscope is a delicate piece of equipment and should be treated with care.

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Preparing specimens for viewing:


Electron Microscopes

Light microscopes are limited to about 2000X by the properties of light. Another type of microscope called an electron microscope uses a beam of electrons instead of light and magnets instead of lenses. Because of the high-energy particles involved, these microscopes cannot be used to view living specimens.

There are two types of electron microscopes:

Comparing the visual range of light and electron microscopes.

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