Cut angles for tuning fork type quartz resonators

摘要

Axes X', Y' and Z' of a resonator are established from the axes X, Y and Z of a quartz crystal by virtue of two rotational movements through angles &phgr; and &thgr;, respectively. The resonator is energized to vibrate in accordance with the fundamental torsional mode. The angles of cut &phgr; and &thgr; are such that the first-order temperature coefficient is zero. The torsional mode may be coupled to a flexural mode in order to render the second-order temperature coefficient zero. The fork tines extend in the X' direction. In other embodiments the tines extend in the Y' direction and the rotation &phgr; and &thgr; are about the X and Z' axes, respectively.