The main components of light microscopes are: eyepiece, lens tube, objective revolver, stage, table, condenser, fine focus, coarse focus, luminous-field diaphragm, light source, base. An eyepiece is that part of an optical system, which is directed to the viewer.

Ocular Lens – The ocular lens, or eyepiece, magnifies the image. It contains a measuring scale called and ocular micrometer. The ocular micrometer has no units. Revolving Nose Piece – Several objective lenses of varying magnification and numerical aperture are mounted on the revolving nosepiece.

For example, optical (light) microscopes are usually equipped with four objectives: 4x and 10x are low power objectives; 40x and 100õ are powerful ones. The total magnification (received with 10x eyepiece) of less than 400x characterizes the microscope as a low-powered model; more than 400x as a powerful one.

Types of Microscopes

• The light microscope. The common light microscope used in the laboratory is called a compound microscope because it contains two types of lenses that function to magnify an object.
• Other light microscopes.
• Electron microscopy.

There are two main types of electron microscope – the transmission EM (TEM) and the scanning EM (SEM). The transmission electron microscope is used to view thin specimens (tissue sections, molecules, etc) through which electrons can pass generating a projection image.

Light Microscopes Visible light passes and is bent through the lens system to enable the user to see the specimen. Light microscopes are advantageous for viewing living organisms, but since individual cells are generally transparent, their components are not distinguishable unless they are colored with special stains.

Here are 50 easy-to-find things to view under a microscope.

• Salt (including different types)
• Sugar.
• Sand (compare from different beaches, if possible)
• Bird seed.
• Different colors of human hair (be sure to look at dyed and natural, and roots)
• Fur from various species.
• Whiskers.
• Onion skin.