A fluorescent lamp or fluorescent tube is a gas-discharge lamp that uses electricity to excite mercury vapor. The excited mercury atoms produce short-wave ultraviolet light that then causes a phosphor to fluoresce, producing visible light. A fluorescent lamp converts electrical power into useful light more efficiently than an incandescent lamp. Lower energy cost typically offsets the higher initial cost of the lamp. The lamp fixture is more costly because it requires a ballast to regulate the current through the lamp.
While larger fluorescent lamps have been mostly used in commercial or institutional buildings, the compact fluorescent lamp is now available in the same popular sizes as incandescents and is used as an energy-saving alternative in homes.
Because they contain mercury, many fluorescent lamps are classified as hazardous waste. The United States Environmental Protection Agency recommends that fluorescent lamps be segregated from general waste for recycling or safe disposal.
Read more about Fluorescent Lamp: Principles of Operation, Phosphors and The Spectrum of Emitted Light, Applications, Lamp Sizes and Designations, Other Fluorescent Lamps, Science Demonstrations
Famous quotes containing the word lamp:
“Thus he struggled, by every method, to keep his light shining before men. Surely the lighthouse-keeper has a responsible, if an easy, office. When his lamp goes out, he goes out; or, at most, only one such accident is pardoned.”
—Henry David Thoreau (1817–1862)