A nixie tube is a type of display device that uses a special type of gas-discharge tube to display numerals or other information. These tubes were commonly used in electronic devices during the 1950s and 1960s, before the widespread adoption of LCD and LED displays.
Nixie tubes consist of a sealed glass tube containing a number of cathodes in the shape of numerals or other symbols. These cathodes are typically made of a mixture of metals such as cadmium and zinc, which emit a warm orange-red glow when they are heated.
When a voltage is applied to the cathodes inside the nixie tube, the gas inside the tube becomes ionized, creating a glowing plasma. This plasma is attracted to the cathodes, causing them to heat up and emit their characteristic orange-red glow.
The voltage applied to the cathodes is controlled by the electronic circuit that drives the nixie tube, allowing the user to display a specific numeral or symbol by turning on the appropriate cathode. Multiple cathodes can be turned on at the same time, allowing the nixie tube to display multiple numerals or symbols simultaneously.
In addition to the cathodes, nixie tubes also contain a number of anodes, which are typically arranged in a circular or rectangular pattern around the cathodes. The anodes are used to create an electric field inside the tube, which helps to control the direction of the plasma and ensures that it is attracted to the cathodes.
Overall, nixie tubes are a fascinating and visually appealing technology that was widely used in electronic devices during the mid-20th century. Despite their obsolescence, they continue to be popular among electronics enthusiasts and vintage technology collectors.