lighting: Functional Selection of Lighting

The incandescent lamp was long the basic light source, and still remains the one in most common use, though it is being superseded by compact fluorescent and LED lamps. While the least expensive to buy, it is the most expensive to own due to its low efficiency and relatively short life. The fluorescent lamp is the second most common light source. It is widely used in factories, offices, stores, and public buildings because it produces far more light for the same expenditure of electricity than do incandescent lamps. Compact fluorescent bulbs that can act as replacements for standard incandescent bulbs are sold for their long life and energy efficiency. However, to many observers the colors of objects illuminated by a fluorescent lamp often appear quite different than they would appear if the objects were illuminated by an incandescent lamp or sunlight. More efficient LED lamps that also are capable of producing a more natural light than fluorescent lamps are increasingly replacing both fluorescent and incandescent lamps, especially in commercial settings. Sodium vapor lamps are used on some highways, as are color-corrected mercury-vapor discharge lamps. Tungsten-halogen lamps are used for lighting sports arenas and stadiums, in automobile headlights, and for residential lighting. Xenon lamps are used in flash photography as well as in cinema projectors and lighthouses.

Sections in this article:

• Introduction
• Functional Selection of Lighting
• Contemporary Lighting Technology
• The Fluorescent Lamp
• The Incandescent Lamp
• Electric Lighting Comes of Age
• The Introduction of Gas as a Fuel
• Early Sources of Artificial Lighting

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

See more Encyclopedia articles on: Technology: Terms and Concepts