Analysis of vibrations in AT-cut quartz crystal plates using a light modulated oscillator

A basic study of a quartz crystal oscillator system in which a quartz crystal resonator (or plate) is used as light modulator is reported. In this oscillator system, the quartz crystal plate is used as a three-port network because the light beam modulated by the dynamic stress of the oscillating quartz crystal plate is used as a feedback loop of oscillations. A quartz crystal oscillator system of high quality is realized. Experimental results on the basic characteristic of the plano-convex AT-cut quartz crystal plate used for the light modulator in the present system are described in detail The dynamic stress distributions and the quality factor Q of the plate are measured by means of a laser probe beam modulation method.