Nixie tube is a kind of ion tube that uses the principle of gas nixie discharge. In 1857, German physicist Heinrich Geissler made the first practical use of this phenomenon, inventing the Geissler tube. In the late 1920s and early 1930s, inventors realized that they could extend the discharge glow from Geissler tubes to the cathode, which could then be shaped to limit the nixie. For example, numbers or words can be displayed using a curved wire as a cathode. So the glow tube was born, but it ...