Seiko released the world's first mass-produced electronic quartz wristwatch, the Astron, in 1969.
The Seiko Quartz-Astron 35SQ was introduced in Tokyo on December 25, 1969. It used a quartz crystal oscillator to keep time and an electronic circuit to divide the oscillator's high-frequency vibrations into regular signals.
Quartz watches were considerably more accurate than most mechanical watches of the period, though the first Astron was expensive and produced in limited numbers compared with later quartz models. As production costs fell during the 1970s, quartz technology spread rapidly through the global watch industry.
The “quartz crisis” transformed traditional watchmaking, especially in Switzerland, by bringing accurate, inexpensive electronic watches to mass markets. Seiko’s Astron name was later reused for newer GPS solar watches.