In April, Joel Spira, inventor and developer of the solid-state electronic dimming device and chairman and founder of Pennsylvania-based Lutron Electronics, donated materials related to the company’s 50-year history to the Smithsonian’s National Museum of American History.

The donation includes an early version of the original solid-state (devices using transistors) Capri dimmer manufactured by Lutron in September 1964. Also part of the donation is a retail display featuring the fully functional dimmer and other Lutron dimmers and lighting control systems that show lighting control developments at the company over the past 50 years.

The museum requested objects and papers that would provide insight into Spira’s career as an inventor. The museum will receive his original inventor’s notebook with more than 100 pages of handwritten documentation and historic photographs as well as product advertisements.
The Lutron materials will join other artifacts in the museum’s Electricity Collection, including experimental lamps from Thomas Edison, dimming light sockets from the 1910s, theatrical lighting controls from the 1920s and many types of lighting switches.

“As the nation’s history museum, we tell the story of this country in all its depth and breadth,” said Brent D. Glass, director of the museum. “Collections such as this one from Lutron help us to understand the continuation of the electrical evolution, the process of invention and the history of business and manufacture.”

In his New York apartment in the late 1950s, Spira developed a way to reduce the light output of an incandescent lamp which extended the life of the lamp and saved electrical energy. The commercialization of the solid-state dimmer has made such control of interior lights affordable for most homes.

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