Crystals That Tell Time
November 20, 2013
On November 3, the majority of the United States moved our clocks back one hour to mark the end of Daylight Saving Time. Most of those clocks contain a quartz crystal oscillator. Thanks to a keystone invention by Warren Marrison in 1927, quartz clock technology remains one of the most accurate ways to keep track of the passing seconds, minutes and hours. Unsurprisingly, it has since become the world’s most widely-used timekeeping technology.
Like many other inventions, the development of quartz clock technology was actually unintended. Canadian-born Warren Marrison, a telecommunications engineer at Bell Telephone Laboratories, initially set out to monitor frequency standards for radio broadcasting. Quartz had long been known to provide an accurate frequency signal for radio transmitters, receivers and computers. In the process of solving one technical problem, Marrison successfully utilized the unique property of quartz to solve another by creating a highly accurate timepiece.
Up until that point, clocks were largely mechanical and relied on a balance wheel or pendulum to keep time. Mechanical wrist watches, in particular, use the force of a spring to power the balance wheel, which oscillates at a constant rate to keep track of the time. To maintain the timekeeping consistency of a mechanical watch, the user winds the spring manually.
Quartz watches, on the other hand, are powered electronically. When charged with an electrical current, quartz oscillates at a highly regular rate, effectively replacing the balance wheel of mechanical watches. Quartz watches exhibited far greater accuracy than mechanical watches, and was indeed a revolutionary development in the history of timekeeping. As technology progressed, the parts required to build a quartz watch not only became smaller, but also less expensive. By the 1980s, quartz watches had completely overtaken the popularity of mechanical watches.
In the years that passed since quartz clock technology was born, watchmakers have continued to strive towards ever more precise methods of tracking time. Two decades after Marrison invented the quartz clock, the atomic clock was invented and is now the epitome of accuracy in timekeeping. However, quartz watches—which vary by only a second every 30 years—are still amazingly accurate. Through a winning combination of incredible reliability and low cost, quartz clock technology continues to survive the test of time.