摘要 |
An electrostatic voltmeter with a microdeflector probe having a base, a flexible finger supported on the base in cantilever fashion, the finger deflecting in response to a potential difference thereacross, separate driven and variable capacitance electrodes on the finger sensing the charge voltage on the surface to be measured, the pickup electrode being electrically coupled to the driven electrode, the resulting charge voltage on the driven electrode changing finger deflection and altering the capacitive relationship between the base and the variable capacitance electrode; a predetermined reference voltage on the base; and a circuit for converting the change in capacitance between the base and the variable capacitance electrode to a signal representing the voltage on the surface. In an alternate embodiment, a second microdeflector is provided which changes capacitance between base and variable capacitance electrode in response to noise, and a control for adjusting the signal in response to the noise signal.
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