Experimental integral compact fluorescent lamp

Description:

As energy prices soared in the 1970s, lamp makers focused research efforts on raising the energy efficiency of electric lamps. A great deal of effort by many researchers went into designing small fluorescent lamps that might replace a regular incandescent lamp. These efforts led to modern compact fluorescent lamps that use bent or connected tubes, but many other designs were tried. This experimental "partition lamp" from 1978 shows one such design.

Soon after the 1939 introduction of linear fluorescent lamps, inventors began receiving patents for smaller lamps. But they found that the small designs suffered from low energy efficiency and a short life-span. Further research revealed 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. That's why fluorescent tubes in stores and factories are usually 8 feet (almost 3 meters) long.

Inventors in the 1970s tried many ways of putting a long arc path into a small lamp. In this case there are thin glass walls inside the lamp, dividing it into four chambers. Each chamber is connected in such a way that the electric current travels the length of the lamp four times when moving from one electrode to the other. So the arc path is actually four times longer than the lamp itself, raising the energy efficiency of the lamp. This unit was made by General Electric for experiments on the concept, though other makers were also working on partition lamps.

While the partition design works, it proved to be expensive to manufacture and most lamp makers decided to use thin tubes that could be easily bent and folded while being made.

Lamp characteristics: No base. Two stem assemblies each have tungsten electrodes in a CCC-6 configuration with emitter. Welded connectors, 3-piece leads with lower leads made of stranded wire. Bottom-tipped, T-shaped envelope with internal glass partition that separates the internal space into four connected chambers. Partition is made of two pieces of interlocked glass and is not sealed into the envelope. All glass is clear. No phosphors were used since the experimenter wanted to study the arc path.

Date Made: ca 1978Date Made: ca. 1978

Maker: General Electric Corporate Research & Development Laboratory

Place Made: United States: New York, Schenectady

See more items in: Work and Industry: Electricity, Energy & Power, Industry & Manufacturing

Exhibition: Lighting a Revolution

Exhibition Location: National Museum of American History

Related Web Publication: http://americanhistory.si.edu/lighting/

Related Publication: Lighting A Revolution

Credit Line: from General Electric Corporate Research & Development Laboratory

Data Source: National Museum of American History

Id Number: 1998.0050.16Accession Number: 1998.0050Catalog Number: 1998.0050.16

Object Name: discharge lampfluorescent lampOther Terms: discharge lamp; Fluorescent

Physical Description: glass (overall material)mercury (overall material)metal (overall material)Measurements: overall: 8 3/4 in x 2 in; 22.225 cm x 5.08 cm

Guid: http://n2t.net/ark:/65665/ng49ca746a5-8d41-704b-e053-15f76fa0b4fa

Record Id: nmah_751184

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