| 摘要 |
An electrostatic voltmeter including a probe having a detector which is resistively coupled into a region bearing ionized air and an electrostatic field or potential to be measured. An ionization source in the form of a radioactive material is carried by the probe housing and ionizes the air in the region of the detector to provide an ionic current flow into the detector in response to the measured electrostatic field or potential. The electrostatic voltmeter further comprises an amplifier having an input and an output and connected for unity gain, the amplifier input being coupled to the detector. The amplifier has a feedback path connected as a voltage reference for the detector to cause the ionic current flow to change in a manner which will drive the amplifier and feedback to reduce the electrostatic field in the vicinity of the detector to zero. When the detector is positioned in non-contacting proximity to a surface bearing a field or potential to be measured, ionic current flows into the detector and drives the amplifier and feedback in a manner reducing the field and therefore the potential difference between the detector and surface to zero so that the amplifier output voltage is driven to the same potential as that on the surface. The electrostatic voltmeter can be employed in an electrostatic control system characterized by relatively fast response.
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