This was the first electronic digital watch, and also the first without any moving parts. Designed in the United States by the Hamilton Watch Company of Lancaster, Pennsylvania and Electro-Data Inc of Garland, Texas, it went into large-scale production in 1972. The watch is quartz-controlled, but has a light-emitting diode (LED) digital display. To conserve battery power, the display is switched on by presing a button, switching off after a few seconds. LED watches were popular for a time, but were eclipsed by the LCD (light crystal display) watches, also introduced in 1972.
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