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:
“A cold and searching wind drives away all contagion, and nothing can withstand it but what has a virtue in it, and accordingly, whatever we meet with in cold and bleak places, as the tops of mountains, we respect for a sort of sturdy innocence, a Puritan toughness. All things beside seem to be called in for shelter, and what stays out must be part of the original frame of the universe, and of such valor as God himself.”
—Henry David Thoreau (1817–1862)