Quartz resonator is called crystal oscillator for short, it is made of quartz crystal with piezoelectric effect.

This kind of quartz crystal flakes will produce mechanical vibration when subjected to an applied alternating electric field. When the frequency of the alternating electric field is the same as the natural frequency of the quartz crystal, the vibration becomes very strong, which is the response of the crystal resonance characteristics.

Using this feature, you can replace LC (coil and capacitor) resonant circuits, filters, etc. with quartz resonators. Because quartz resonators have the advantages of small size, light weight, high reliability, and high frequency stability, they are used in household appliances and communication equipment.