Seiko Epson (then Suwa Seikosha but referred to below as Epson) succeeded in developing the world's first commercial quartz watch. That was more than half a century ago, in 1969. Today, quartz watches account for about 96%^* of all the watches manufactured globally. The technology developed for the first quartz watch continued to evolve and eventually laid the foundations for Epson's crystal device and semiconductor businesses. In addition to watches, this technology is found in application as varied as computers, digitally controlled home appliances, mobile phones, automobiles, and industrial equipment.
Read on to learn more about the technology inside the world's first quartz watch.

^* The 96% figure was calculated based on a 2017 estimate of watch production quantity by the Japan Watch Association.

The following is a simplified explanation of the operating mechanisms in a quartz watch.
First, the crystal unit housed in the oscillator 2. oscillates at a frequency of 32,768 Hz on the electricity sent from 1. the battery. This frequency is divided by a divider circuit 3. so that it is brought down to one signal per second. Furthermore, this signal is converted to mechanical rotary motion by step motor converter 4., the indicating mechanism 5. moves the hand by one index per second, and this motion is then transmitted to the minute and hour hands.

Quartz clocks became popular from almost the moment they first appeared, but they were less than ideal. That was because the crystals needed to be kept at a constant temperature to maintain stable frequency output. For this reason, In 1959 early quartz clocks had a thermostatic function that made them very large(such as a locker size:1.3m x 2.1m) and increased their power consumption.

Epson thus began research and development work on technology that would reduce the size and energy consumption of quartz timepieces without sacrificing accuracy. We replaced the bulky vacuum tubes with transistors, got rid of the thermostatic chamber, and developed a temperature compensating device using a variable capacitor to realize a much smaller quartz clock. After the company was tasked with developing an official timekeeping system for the 1964 Tokyo Olympics, the speed of development accelerated. This work culminated, in 1963, with the development of a portable quartz clock, the Seiko Crystal Chronometer QC-951. Development speed picked up still further, and three years later, in 1966, Epson announced a pocket-sized quartz watch. Then, in 1969, we launched the world's first quartz wristwatch, the Seiko Quartz Astron 35SQ.

It was precision processing and electronics technologies that enabled Epson to reduce the size of quartz timepieces.
There were three technologies that were key.

The electrical signal emitted by a quartz oscillator unit must be divided and the drive waveform shaped before it can be converted into mechanical rotational motion. Epson developed a watch IC that did just that. This hybrid IC was made possible by some outstanding craftsmen & women who manually soldered 76 transistors and 84 resistors 29 capacitors total 189 elements onto a ceramic substrate.

We continued development believing that a stable supply of C-MOS ICs would be essential for expanding and stabilizing our wristwatch business. So, we sounded out IC manufacturers. However, the answer was always that they couldn't help because there was no demand for ultra-low power devices. That being the case, we decided to pursue C-MOS IC development and manufacturing by ourselves. Ultimately, we succeeded in developing and volume-producing C-MOS ICs for ultra-low power watches, in 1971.

These C-MOS IC for watches ran on one-third to one-quarter of the power used by ordinary ICs at that time, so, over time, their use expanded beyond watches and into consumer electronics, such as home appliances, computers, and cell phones, as well as into automobiles and other devices that support a wide range of industries.

Motors are used in timepieces to convert electric signals that are precisely regulated in a once-per-second rhythm by an IC into mechanical motion that is transmitted through gears to the second, minute, and hour hands that we see on the dial. However, conventional cylindrical motors are large and difficult to mount in a wristwatch. Therefore, we took on the challenge of developing a new open-type motor, one whose parts would be separated and arranged in a dispersed layout. What Epson developed was an ultra-compact open-tape step motor consisting of a separate coil, stator, and rotor.
In addition to the mechanism changes, the new motor had an ultra-fine wire coil, a high magnetic force rotor magnet, and an optimized control method for driving the motor. These also resulted in lower power consumption.

The Seiko Quartz Astron 35SQ drew a great deal of attention around the world. That was because whereas even the most accurate mechanical wristwatches lost or gained about 20 seconds a day, a quartz wristwatch, with a daily rate of ±0.2 seconds (and monthly rate of ±5 seconds) was 100 times more accurate. The response was such that an article about the Quartz Astron 35SQ even appeared in the New York Times. There was also a media story that called the product "a revolution" in the history of horology.

In addition to transformative technology, the Seiko Quartz Astron 35SQ made an impact and earned stellar reviews for implementing innovative ideas and for design aesthetics, including a battery cover that made battery replacement easy and an elegant appearance thanks to a round movement.

Epson published patents detailing its quartz watch technology. This resulted in the global spread of analog quartz watches. Currently, quartz watches account for about 96% of all watches manufactured around the world. In other words, Epson's technology gave people in every corner of the Earth access to accurate times.

Epson's quartz watch has been the subject of numerous awards, and Epson has earned recognition for both the technology and the publication of patents that were opened to the public. And today, even more than half a century since its advent, the technology continues to be revered as a beacon of Japanese technology.

• 2002 : Corporate Innovation Recognition Award, the American Institute of Electrical and Electronics Engineers (IEEE)
• 2004 : Milestone Award, the IEEE
• 2014 : Mechanical Engineering Heritage registration, Japan Society of Mechanical Engineers
• 2018 : Essential Historical Materials for Science and Technology, National Museum of Nature and Science

Epson went on to further advance key technologies to create products that are even smaller and draw less power yet deliver exceptional performance. Epson's crystal devices and semiconductor businesses both grew out of quartz watch development. Compactness and power saving were the watchwords that guided development work on the quartz watch. These words express ideals to which we still ascribe to this day and which are embodied by Epson's efficient, compact, and precision technologies.

* The statement that quartz watches account for 96% of all watches manufactured is based on a 2017 estimate of watch production quantity by the Japan Watch Association.