Experimental fluorescent lamp
date: label: date made
content: ca. 1934
label: Date made
content: ca 1934
name: label: manufacturer
content: General Electric
notes: label: Description
content: The development of practical fluorescent lamps took decades, and many researchers contributed. Julius Plucker and Heinrich Geissler made glowing glass tubes in the 1850s, about the time George Stokes discovered that invisible ultraviolet light made some materials glow or "fluoresce." Alexandre Edmond Becquerel put fluorescent materials in a Geissler tube in 1859, though his tubes did not last long. Carbon dioxide-filled tubes by D. McFarlan Moore and mercury vapor tubes by Peter Cooper Hewitt around 1900 gave practical experience with gas-filled, discharge lamps and inspired the neon tubes of Georges Claude.
label: Description
content: In 1926 Friedrich Meyer, Hans Spanner, and Edmund Germer of Germany patented an enclosed glass tube containing mercury vapor, electrodes at either end, and a coating of fluorescent powders called phosphors. This incorporated all of the features we see in modern fluorescent tubes, but their employer did not pursue development. William Enfield of General Electric saw phosphor-coated neon tubes in France in the early 1930s, and heard that European researchers were developing a fluorescent lamp. An especially urgent 1934 letter from a consultant, Nobel-laureate Arthur Compton, coming on the heels of European breakthroughs in low-pressure sodium and high-pressure mercury lamps, spurred both GE and its licensee Westinghouse into combined action.
label: Description
content: Enfield created a team led by George Inman, and by the end of 1934 they made several working fluorescent lamps, including the one seen here. To save time, the team adopted the design of an existing tubular incandescent lamp in order to make use of available production equipment and lamp parts. Speed was important. In addition to European competitors, American companies like Sylvania were also working on fluorescents. A second GE group under Philip Pritchard worked on production equipment. Other GE groups in Schenectady and in Ft. Wayne assisted in developing ballasts and resolving problems of circuit design.
label: Description
content: In 1936 GE and Westinghouse demonstrated the new lamp to the U.S. Navy (that lamp is in the Smithsonian's collection). The public finally saw fluorescent lamps in 1939 at both the New York World's Fair and the Golden Gate Exposition in San Francisco. These early lamps gave twice the energy efficiency of the best incandescent designs. Production of fluorescent lamps, slow at first, soon soared as millions were installed in factories making equipment for the American military during World War 2.
label: Description
content: Lamp characteristics: Double-ended without bases. Flat presses with an exhaust tip near one press. A tungsten electrode, CC-6 configuration coated with emitter, is set at either end. A mercury pellet is loose inside the lamp. The clear T-7 glass envelope has a phosphor coating covering about 3 inches (8 cm) of the lamp near the center.
place: label: Place Made
content: United States: Ohio, Cleveland
setName: label: See more items in
content: Work and Industry: Electricity
label: See more items in
content: Energy & Power
label: See more items in
content: Industry & Manufacturing
label: Exhibition
content: Lighting a Revolution
label: Exhibition Location
content: National Museum of American History
publisher: label: Related Publication
content: Bright, Jr., Arthur A.. The Electric-Lamp Industry: Technological Change and Economic Development from 1800 to 1947
label: Related Publication
content: Thayer, Richard N.. The Fluorescent Lamp: Early U.S. Development
label: Related Publication
content: Lighting A Revolution exhibition website
label: Related Web Publication
content: http://americanhistory.si.edu/lighting/
creditLine: label: Credit Line
content: from General Electric Lighting Company, thru Terry K. McGowan
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: 1997.0388.41
label: accession number
content: 1997.0388
label: catalog number
content: 1997.0388.41
objectType: label: Object Name
content: discharge lamp
label: Object Name
content: fluorescent lamp
label: Other Terms
content: discharge lamp; Fluorescent
physicalDescription: label: Physical Description
content: glass (overall material)
label: Physical Description
content: mercury (overall material)
label: Physical Description
content: tungsten (overall material)
label: Measurements
content: overall: 14 1/2 in x 7/8 in; 36.83 cm x 2.2225 cm