Quartz Resonators vs Their Environment: Time Base or Sensor?

This work discusses the effects of temperature, force, and acceleration on the frequency of quartz thickness shear mode resonators. Historically, workers in the frequency control industry have tried to reduce these effects. Some of the physical principles will be discussed. Turning the problem around, sensitivity to these effects can be maximized to develop sensors for temperature and pressure. Advantages of such sensors include inherently digital format, high resolution, high accuracy, and long-term stability. This work reviews the physical principles involved in the operation of some devices used down-hole in the oil and gas service industry.