Cold cathode ionization vacuum gauge

Cold-cathode ionization vacuum gauges (Penning vacuum gauges)... 

Thermocouple vxuum gauge Bimetallic vacuum gauge Thermistor vacuum gauge Cold-cathode ionization vacuum gauge... 

In all those measurement instruments which use the ionization of gas molecules as the measurement principle (cold-cathode and hot-cathode ionization vacuum gauges), strong magnetic leakage fields or electrical potentials can have a major influence on the pressure indication. At low pressures it is also possible for wall potentials which deviate from the cathode potential to influence the ion trap current. 

Gauges. Because there is no way to measure and/or distinguish molecular vacuum environment except in terms of its use, readings related to gas-phase concentration ate provided by diaphragm, McCleod, thermocouple, Pitani gauges, and hot and cold cathode ionization gauges (manometers). 

A precision aneroid manometer is used for measurements in the 760— 1 torr range. Thermocouple gauges are used in the 1 — 1 x 10 3 range. A cold cathode ionization gauge is used in the high vacuum range down to 10-6 torr. 

Cold Cathode Ionization Gauges, Journal Vacuum Science and Technology, A, 9, pp. 1977-1985 (1991). 

The cold cathode ionization gauge has offsetting advantages relative to the hot cathode type. It is insensitive to mechanical vibrations, is not susceptible to an inrush of air in the event of a vacuum accident (that can destroy the healed filament in the hot cathode type) and is less susceptible to harm from contaminants. 

Cold cathode ionization gauge (vacuum technology) An ionization-type vacuum gauge where the electrons for ionization are usually produced by a secondary electron-emitting surface or a radioactive material. Often uses a magnetic field to increase the path length of the electrons. 

Fig. 7.10. Cutaway of a cold cathode (Penning) gauge. The wire anode (A) is connected through a ceramic insulator (i) to the high-voltage lead (H). Under the influence of the magnetic field created by M, the elcclrons travel a long spiral path between the body and the anode. The current, which arises from electrons and positive ions of the ionized gas molecules, is related to the pressure. The open end (C) is attached to the vacuum system.

Huang JX, Chen J. et al., Bayard-Alpert ionization gauge using carbon-nanotube cold cathode. Journal of Vacuum Science and Technology B, 2007. 25(2) 651-654. 

Vacuum gauge, ionization cold cathode gauge A vacuum gauge that uses an ion current formed by electron-atom collisions as an indicator of the gas pressure (density). The electrons are formed as secondary electrons from ion bombardment. 

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