Last week, the Smithsonian Institution’s National Museum of American History celebrated the dimmer as part of a permanent exhibition on lighting.

Naturally, then, the inventor of the solid-state dimmer, Lutron founder Joel Spira, would be celebrated as well.

During a press event and subsequent gala that attracted government officials, loyal customers, family and friends, Spira formally signed over the following artefacts to the Smithsonian:

  • Oldest Capri dimmer in the Lutron archives (circa 1964), first solid-state dimmer
  • Capri marketing display from the 1960s
  • Capri advertisement from the 1960s
  • Joe Spira’s first journal, “Notebook A”
  • Nova dimmer (1971), first linear slide dimmer
  • RanaX (1989), first IR dimmer and remote control
  • NeTwork (1990), first whole-house lighting control system
  • GRAFIK Eye (1993), first customizable dimming system for different light sources
  • RadioRA system (1997), first two-way RF whole-house lighting control system
  • Vierti(2007), single-touch dimmer
  • Skylark eco-dim dimmer (2008) that limits light output to 85%
  • Serena (1993) motorized window shading system
  • A Dimmer is Born

    So just how did Spira invent the dimmer?

    A number of years ago, someone showed him a solid-state device called a silicon controlled rectifier (SCR), which is about the size of a large pea. The SCR worked by chopping out a varying portion of the 60-cycle sine wave.

    During World War II in the Navy, Spira had a device for secret radars that did the same thing as the SCR, but was much larger – about the size of a milk carton.

    Struck by the device’s ability to control electrical power, he figured he could put it in a wallbox and dim an ordinary light bulb.

    While it wasn’t the first dimming device, it was the only one smaller than a breadbox and thus the only one that could fit inside a standard wallbox.

    Spira received a patent on the dimmer in 1962.