IONIZATION VACUUM GAUGE AND CONTROL DEVICE

摘要

The ionization vacuum gauge according to one embodiment of the present invention is provided with a gauge head and a control unit. The control unit has a drive circuit, a grid power source, an ionic current detection circuit, and a potential restriction circuit. The drive circuit includes a drive power source for driving an electron emission source, and controls the drive power source such that an emission current flowing between the electron emission source and the grid becomes constant. The grid power source maintains a grid at a prescribed grid potential. The ionic current detection circuit detects an ionic current flowing into a collector. The potential restriction circuit is connected between the drive circuit and the grid power source, and maintains the potential of the electron emission source within a prescribed range from a first potential that is higher than the potential of the collector to a second potential that is lower than the grid potential.