342:. Unlike theatrical dimmers, Spira's standalone device was small enough for home application. Thyristor based designs (compared to rheostats) instead "chop" the incoming AC mains waveform, quickly switching their level of conductance (and the attached lights' brightness). Compared to a rheostat-based circuit, the use of a thyristor greatly increases efficiency, as far less waste heat is generated. Dimming lights with a solid state dimmer also reduces total power draw, unlike rheostat dimmers. Spira's design (and most modern dimmers) rely on the use of AC power, and on the characteristics of incandescent lights. Most importantly, incandescent lights take time to cool down when switched off, and so are much less prone to flickering than other kinds of lighting. LED lights are especially prone to flickering when used with traditional dimmers.
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370:, in 1961. The privately held firm, whose headquarters remain there today, has grown into an international manufacturer and distributor not only of dimmers, but also of motorized and automated window-covering systems, as well as lighting fixtures and temperature controls.
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Spira became—as a result of his discovery—best known for his initial, seminal invention: the first successful solid state-electronic dimmer. He filed for a patent on July 15, 1959 (U.S. 3,032,688). On the basis of the dimmer alone, he and his wife
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for use in homes around the United States and led his Lutron
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switch. During his research, he recognized that the device could also be employed to vary the intensity of light powered by
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laboratory to concentrate on refining the device. Spira then went on to conduct experiments on a ping-pong table in his
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In the 1950s, Spira worked for an aerospace company, where he was assigned to develop a reliable trigger for
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Spira headed the firm for 54 years and more recently became chair of the board and research director.
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invention of the first solid state-electronic dimmer and founder of Lutron
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Who's who in
Finance and Industry - Inc. Marquis Who's Who - Google Books
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510:"Lutron: Joel Spira's Inventions 'Make People's Lives Better'"
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apartment in New York City, leading to his marketable design.
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185:(March 1, 1927 – April 8, 2015) was an American
422:"Joel S. Spira Obituary (1927 - 2015) Morning Call"
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381:Spira died April 8, 2015, at the age of 88 from a
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109:Learn how and when to remove this message
403:American Society of Mechanical Engineers
168:inventor, entrepreneur, business magnate
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565:"Patent US3032688 - Dimming device"
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314:solid state
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600:2018-09-06
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408:References
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463:cite book
347:aerospace
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326:Lighting
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282:May 2023
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642:. ASME
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