A NEW GENERATION The quartz movement and the advent of the era of high precision

The year was 1969. As well as the mechanical chronograph and the V.F.A. (Very Fine Adjusted) movement, which delivered Seiko’s highest yet level of precision for a mechanical movement, Seiko also released the world's first quartz wristwatch, Quartz Astron, the watch that changed the way the world told time. It was perfectly in tune with its age. This was the era of rapid and dramatic advancements in science and technology which enthralled the public, as illustrated by the worldwide fascination with, for example, Apollo 11's moon landing. The Quartz Astron not only matched the zeitgeist but brought high technology within the reach of all.

Before and after the launch of the Quartz Astron, the goal of ever greater accuracy drove the Seiko team onward. The Quartz Astron was accurate to within ±5 seconds a month and it seemed to be a tough challenge to beat this already high new standard. Thanks to the highly precise vibration rate of the quartz crystal oscillator, the Quartz Aston quartz mechanism could be precise to a second, but the resonance frequency of quartz oscillators varied with temperature so this level of accuracy was not initially achievable in everyday use.

To meet this challenge, the Seiko engineers came up with an ingenious solution. Two quartz oscillators were set alongside each other; one was used to detect the temperature so that variations due to temperature change in the other oscillator could be compensated for. Completed in 1978, this movement, named "Twin quartz," raised the bar once again. The Grand Twin Quartz delivered a precision rate of ±10 seconds a year, and the Seiko Superior Twin Quartz had an even higher degree of accuracy at ±5 seconds a year. The challenge was well and truly met.