Electrode Design of Single Crystal Lithium Niobate Piezoelectric Disk Gyroscope

Abstract

This paper reports optimization of electrode arrangement of piezoelectric disk gyroscope using single crystal lithium niobate (LN). The disk was fabricated from a 155°-Y cut LN wafer in which the elastic compliance is uniform in any in-plane directions to realize mode-matching in two wineglass modes for gyroscope operation. To mitigate anisotropic piezoelectric properties of the LN wafer, the electrode patterns on both sides of disk were optimized. For 45°-mode operation, eight segmented electrodes were designed by considering the opposite polarity of the transverse piezoelectric constants d31 and d32, whereas the 0°-mode was oscillated with single electrode. Angular rate was successfully detected using LN disk resonator of the 25.8-mm-diameter and 330-μm thickness.