Ignitron

Part of speech: noun

Definitions

1. A specialized electronic device that utilizes a gas-filled tube to control electric current through an ionized gas medium
2. A type of switch that can be operated by a low-level control signal, enabling high voltage circuits to function
3. A component in electronics that usually allows for high power and fast switching, playing a critical role in specific applications like power regulation or conversion

Etymology: The ignitron is named for what it does, not for any famous inventor. Its name comes from "ignite" with the suffix "-tron," the same ending used in electronic devices such as the electron and the thyratron. The "-tron" element is a conventional coinage for electron tubes and related devices, so the word reads as "something that ignites," which is close to the device's actual function: it starts a conducting arc inside a mercury-filled tube. The device works by using a pool of liquid mercury as its cathode. A small igniter electrode, dipped into the mercury, creates a spot of vapour that starts the main discharge. Once triggered, the tube conducts heavy currents, and the ignitor-based name reflects this starting action. Because the arc can be switched on rapidly, the device found use in high-power switching and rectification.

Synonyms: thyratron, thyristor, vacuum tube rectifier