microscope: Modified Compound Microscopes

The ultramicroscope is an apparatus consisting essentially of a compound microscope with an arrangement by which the material to be viewed is illuminated by a point of light placed at right angles to the plane of the objective and brought to a focus directly beneath it. This instrument is used especially in the study of Brownian movement in colloidal solutions (see colloid). The phase-contrast microscope, a modification of the compound microscope, makes transparent objects visible; it is used to study living cells. The television microscope uses ultraviolet light. Since this light is not visible, the apparatus is used with a special camera and may be connected with a television receiver on which the objects (e.g., living microorganisms) may be observed in color.

Sections in this article:

• Introduction
• Electron Microscopes
• Modified Compound Microscopes
• Development and Uses
• Computation of Magnifying Power
• Compound Microscopes
• Simple Microscopes
• Bibliography

The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2024, Columbia University Press. All rights reserved.

See more Encyclopedia articles on: Technology: Terms and Concepts