GleichstromGlühentladungen

Gleichstromglühen, often translated as direct current glow discharge, refers to a type of electrical discharge that occurs in a gas when a direct current is applied across it. This phenomenon requires a specific pressure range within the gas, typically between atmospheric pressure and a high vacuum. When the voltage between two electrodes in a gas exceeds a certain threshold, known as the breakdown voltage, the gas begins to ionize. This ionization process allows current to flow, and in the case of Gleichstromglühen, it results in a luminous, glowing plasma.

The glow discharge is characterized by distinct regions of light and electric field strength. The cathode, where electrons are emitted, is often surrounded by a luminous layer. Further away from the cathode, a region of darkness called the Faraday dark space can be observed, followed by a positive column of plasma that extends towards the anode. The color of the glow depends on the type of gas used and the pressure. Common applications for direct current glow discharges include lighting, such as in neon signs and fluorescent lamps, and in gas lasers. They are also utilized in various industrial processes like surface treatment and sputtering. The stability and controllability of the glow discharge make it a valuable phenomenon in scientific research and technological applications.