Integral Compact Fluorescent Lamp

Integral Compact Fluorescent Lamp

Usage conditions apply
An unusual looking type of compact fluorescent lamp (CFLs) has spiral tubes, like this "Spiralux" lamp made by Duro-Test in 1996. Several manufacturers developed and now produce spiral CFLs. While the equipment to make these spiral tubes proved expensive to develop, the design addresses two problems.
CFL engineers faced a problem stemming from the fact that energy efficiency in fluorescent lamps depends in part on the distance the electric current travels between the two electrodes, called the arc path. A long arc path is more efficient than a short arc path. But most residential fixtures are designed to accept lamps the size of ordinary incandescent bulbs. So CFLs have been made with a variety of bent, folded, and connected tubes--all intended to put a long arc-path into a small lamp, the spiral design being one such.
The second problem centered on how light generated by the lamp interacted with shades and reflectors on fixtures. Most incandescent lamp fixtures are designed to use frosted or so-called soft white lamps. The coatings prevent the filament from being seen, making it look like the entire glass bulb is glowing. Shades and reflectors used in regular fixtures are designed using the science of optics to spread and direct the light in predictable patterns. CFLs, with their glowing tubes, are not shaped correctly for regular fixtures, causing light from the fixtures to be emitted in undesired patterns. Spiral CFLs closely mimic the shape of a glowing incandescent lamp so the optical design of the fixture operates as intended.
Lamp characteristics: Brass, medium-screw base with plastic skirt and glass base-insulator. Spiral-shaped discharge tube with internal phosphor coating, mercury, and two tungsten electrodes. The shape is intended to simulate an ordinary A-lamp.
Object Name
discharge lamp
fluorescent lamp
date made
ca. 1996
Date made
ca 1996
DURO-TEST Corporation
Place Made
United States: New Jersey, Bergen
Physical Description
plastic (overall material)
glass (overall material)
mercury (overall material)
metal (overall material)
overall: 5 in x 2 1/2 in; 12.7 cm x 6.35 cm
ID Number
catalog number
accession number
Credit Line
from Duro-Test Corporation
See more items in
Work and Industry: Electricity
Energy & Power
Lighting a Revolution
Exhibition Location
National Museum of American History
Data Source
National Museum of American History
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