Cold Cathode

A cold cathode is a cathode, an electrode that emits electrons, which is not electrically heated by a filament. They are used in gas discharge lamps such as neon lamps, discharge tubes, and some types of vacuum tube. The other type of cathode is a hot cathode, which is heated by a filament which has electric current passing through it. A cold cathode does not necessarily operate at a low temperature; it is often heated to its operating temperature by other methods, such as the current passing from the cathode into the gas.

Read more about Cold Cathode:  Cold-cathode Devices, Lamps, Details

Famous quotes containing the word cold:

    One ... aspect of the case for World War II is that while it was still a shooting affair it taught us survivors a great deal about daily living which is valuable to us now that it is, ethically at least, a question of cold weapons and hot words.
    M.F.K. Fisher (1908–1992)