Kylmäkatodiputki

A kylmäkatodiputki, or cold cathode tube, is a type of gas-discharge lamp that produces light by passing an electric current through a gas at low pressure. Unlike hot cathode tubes, such as fluorescent lamps, cold cathode tubes do not require a heated filament to initiate the discharge. Instead, a high voltage is applied between two electrodes, causing the gas within the tube to ionize and emit light.

These tubes typically contain a low-pressure inert gas, such as neon, argon, or a mixture of gases. When the voltage exceeds the breakdown potential of the gas, electrons are accelerated and collide with gas atoms, causing further ionization and a cascade effect. This process releases photons, resulting in visible light emission. The color of the light depends on the type of gas used and any phosphors that may be coated on the inside of the tube.

Cold cathode tubes are known for their long lifespan, durability, and ability to start quickly. They are often used in applications where reliability and longevity are crucial, such as backlighting for displays, signage, and specialized lighting fixtures. Their compact size and ability to operate in a wide range of temperatures also contribute to their versatility. While they generally consume more power than their hot cathode counterparts, their extended operational life can offset this disadvantage in certain scenarios.