By Isaiah David | Updated Mar 24, 2022
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Piezoelectric crystals, such as quartz, generate an electric charge when mechanically stressed—compressing, striking, or bending. Conversely, applying an electric field induces a tiny change in shape. This bidirectional conversion of mechanical energy to electrical energy underpins a wide range of technologies.
In quartz clocks and timers, a thin slice of quartz vibrates at a highly stable frequency determined by its dimensions. The crystal’s oscillations produce a stream of electrical pulses. An electronic oscillator supplies a small amount of power to keep the crystal oscillating, and the resulting pulse count is used to measure time with millisecond accuracy.
Piezoelectric pickups capture acoustic vibrations by converting them into electrical signals. The device—typically a flexible strip bonded to the instrument—generates a current proportional to the sound waves, allowing direct recording or amplification. Conversely, piezoelectric speakers use an applied voltage to flex the material, creating air pressure waves that we hear as sound.
Piezo igniters are the force behind most push‑button lighters, gas furnaces, and stove burners. When the button is pressed, a spring‑powered hammer strikes the crystal, generating a high‑voltage pulse that arcs between two electrodes. The resulting spark ignites the gas, offering a reliable and chemical‑free ignition source.
