Piezoelectric devices in Japan

Abstract

Quartz is still one of the most important piezoelectric materials, but the field of piezoelectric devices has seen great progress due to discovery and development of new excellent materials, especially piezoelectric ceramics consisting of ferroelectric compounds.The first practical devices made of barium titanate ceramics in Japan were ultrasonic transducers for fish-finders. At the beginning of the piezoelectric-ceramics-age, many other devices such as tuning forks, vibration reeds, and mechanical filters driven by piezoelectric ceramics were studied, but all of these devices were brought into production only after the more stable and efficient ceramic material, lead zirconate titanate ceramics, had been established. At present, the ceramic filters are mass-produced and enjoy a larger market than any other piezoelectric devices.In this paper, a brief history and the present status of research and development of piezoelectric materials and devices in Japan are described with some considerations of various devices in the fields of, among others, ultrasonic transducers, audio transducers, filters, resonators, delay lines, ignitors and piezoelectric transformers.