Electronic Gas Igniter

The gas lighter is mostly cylindrical in shape and consists of a piezo-electric crystal over which a spring-loaded hammer is placed. The hammer and spring set up is attached to a button. When this button is pressed, the hammer is moved away from the piezo-electric crystal. When the button is pressed over a limit, the spring releases the hammer. The hammer hits the piezo-electric crystal. Due to piezo-electric effect, a high voltage is generated in the range of 800 volts. The lighter is wired in such a way that this whole voltage is applied in a small region of air gap between two metallic points. Due to high voltage generated, the air is ionized and acts as a path for the discharge. This electric discharge is the spark which when exposed to the combustible gas from the stove ignites it to  produce flame. In gas lighters, piezo-electric ceramics like lead zirconate titanate also known as PZT are used due to their low cost and high sensitivity.