By most accounts, the first LCD (liquid-crystal display) wristwatch was the 1972 Gruen Teletime, a four-digit, segment-display timepiece that did exactly one thing—it told the time. In 1973, Seiko released the world’s first six-digit LCD quartz wristwatch (the extra two digits displayed seconds), and in 1974, Casio gave the world the Casiotron, whose digital chronometer allowed the watch to deliver calendar functions to its wearer.
LCD wristwatches delivered on the technological breakthrough promised by watches with LED, or light-emitting diode, displays, which had been introduced a few years earlier. As their name suggests, LEDs project light, and while we associate LEDs with energy efficiency today, when the Pulsar LED wristwatch was introduced by Hamilton a few years before LCD wristwatches debuted, the wearer had to press a button to see the time, otherwise the juice in the watch’s battery would run out. LCDs were always on, and they were much cheaper to produce and own.