There are many types of microscopes, the most common and first to be invented is theoptical microscope which uses light to image the sample. Other major types of microscopes are the electron microscope (both the transmission electron microscope and the scanning electron microscope) and the various types of scanning probe microscope.
Microscope
1. An optical instrument, consisting of a lens, or combination of lenses, for making an enlarged image of an object which is too minute to be viewed by the naked eye.
Parts and Specifications Historians credit the invention of the compound microscope to the Dutch spectacle maker, Zacharias Janssen, around the year 1590. The compound microscope uses lenses and light to enlarge the image and is also called an optical or light microscope (vs./ an electron microscope). The simplest optical microscope is the magnifying glass and is good to about ten times (10X) magnification. The compound microscope has two systems of lenses for greater magnification, 1) the ocular, or eyepiece lens that one looks into and 2) the objective lens, or the lens closest to the object. Before purchasing or using a microscope, it is important to know the functions of each part.
Eyepiece Lens: the lens at the top that you look through. They are usually 10X or 15X power.
Tube: Connects the eyepiece to the objective lenses
Arm: Supports the tube and connects it to the base
Base: The bottom of the microscope, used for support
Illuminator: A steady light source (110 volts) used in place of a mirror. If your microscope has a mirror, it is used to reflect light from an external light source up