Patent attributes
A method and a device for measuring ultrahigh vacuum are disclosed. The method includes providing a vacuum cold cathode pressure gauge and varying a voltage on an anode of the pressure cell with pressure in such a way that an ion current flow is maintained substantially at its maximum value at all times. A voltage-controlled source either (1) preliminarily scans a whole voltage range, for example, between 1 kV and 12 kV, in a relatively short time, and subsequently sets the source to the voltage, at which the current is substantially at its maximum value or (2) based on a calibration of the gauge, sets the voltage, for a given pressure, to the value that has been previously stored as substantially optimal. The device operates at a voltage that varies with pressure in such a way that the ion current is maintained substantially at its maximum value at all times. The device is characterized in that an anode of the pressure gauge cell is connected to a voltage-controlled source capable of providing a varying voltage.