Temperature sensor based on quartz tuning-fork resonator

A miniature thermo-sensitive quartz tuning-fork resonator (TSQFR), working in the flexural vibration mode as a temperature sensor, has been expressed. This type of resonator, designed with a new doubly rotated ZYtw-cut, the rotation angle Φ and θ of which must be in the range 110°±1° and 14°±2°, shows nearly a linear response with a sensitivity between 53 ppm°C^-1 and 59 ppm°C^-1 with temperature range from -30 to 150°C. Precise temperature versus frequency analyses of the resonators has been carried out and a least mean squared (LMS) curve fitting algorithm can be used to compute the temperature values quantitatively. Experimentally, the sensor showed an accuracy of 0.05°C with a resolution of 10^-3°C for a 2 s response time.