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Ch. 5 Microscopes

Types of Microscopes

1. Light (Optical) Microscopes:

Use 2 lenses to magnify object.

2. Electron Microscopes:

Microscopes that use electrons to increase magnification and resolution of very small objects. Powerful electron microscopes allow viewing of larger atoms. Electrons focus the view. Only dead specimens may be viewed.

Resolution: The minimum distance 2 points can be apart & still be seen as 2 pts. Electron microscopes have greater resolution as they use electrons that have a shorter wavelength than visble light.

Magnification: How much larger the viewed image appears than its actual size.

Advantages of Light & Electron Microscopes
Light Microscope Electron Microscope
a. Color a. Greater magnification (See smaller objects.)
b. Greater field of view b. Greater resolution (Finer details seen.)
c. Examine live materials (See movement & behavior.)  
d. Easy prep of slide  
   
Types of Electron Microscopes

A. Transmission Electron Microscope:

Electrons pass through object.Tiny items inside an object are seen in great clarity.

B. Scanning Electron Microscope:

Electrons bounced off surface of object viewed. Outer surfaces seen in clear view with great depth of field.

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