The quartz watch, developed in 1969, revolutionized the conventional concept of watches. This is a watch that has a crystal oscillator at its core for accuracy. The crystalline body of a crystal cut to a fixed shape has a characteristic to generate steady vibration if voltage is applied to it.
Through the ages, the idea has existed that this crystal-specific electrical property is used for a crystal oscillator to be the standard of timekeeping accuracy of watches. However, to take advantage of quartz crystal, whose excellence had been demonstrated in terms of accuracy, in a small world
"watch," there were many barriers that had to be overcome.