The lamp seen in these images is an experimental tungsten halogen lamp made by General Electric (probably) in the early 1990s. The markings (visible above) read: “HALOGEN * 120V * 90W.” The GE logo is molded in the center circle. The lamp features a very thick and heavy glass envelope surrounding a quartz capsule mounted in the center of the lamp. The capsule contains a halogen gas and a tungsten filament.

Tungsten halogen is a special type of incandescent lamp that uses a gas to chemically return evaporated tungsten to the filament. These lamps are more energy efficient and longer lasting than ordinary tungsten incandescent lamps. They are also more expensive, although rising electricity costs and recent legislation have resulted in tungsten halogen displacing many regular lamps in the market.

An aspect of tungsten halogen that has stimulated extensive research is the possibility that the internal capsule might explode in use. Although this is only a remote possibility, various safeguards have been evaluated by lamp makers. The lamp seen here shows one such safeguard adopted by several manufacturers. The heavy glass envelope is designed to contain any shards should the quartz capsule fail. Other experimental halogen designs in the Smithsonian’s collection include one lamp with a loose filling of glass wool and another with two 60V halogen capsules in series.

Remember–if you have important documents, photographs, objects, or other historical materials that show aspects of the production of electric lighting during the past 30 years, you can describe them on the “Collecting History from Producers” form. Such materials will help us better understand how events and trends of the recent past have influenced the history of this important technology. And with your help we can build a more complete collection to pass on to future generations.

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© 2001 Smithsonian Institution
Last Updated: January 2001