Microdeflector probe for electrostatic voltmeter
US4835461A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 13, 1984 |
| Grant date | May 30, 1989 |
| Priority date | — |
| Expiry date | Apr 13, 2004 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N1/028
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An electrostatic voltmeter with probe for measuring the charge on a surface, the probe comprising a microdeflector unit having a base; a flexible finger supported on the base in cantilever fashion, the finger deflecting in response to a potential difference thereacross; means to bias the base to a predetermined potential; a sensing electrode on the finger having a side positionable in spaced relation to the surface, the capacitive relation established creating a charge representative of the charge on the surface on the sensing electrode causing deflection of the finger; means to impinge a beam of light on the finger; and a detector disposed to detect reflection of the beam by the finger on predetermined deflection of the finger corresponding to a preset charge measured on the surface. In a second embodiment, a feed-back loop is provided; in a third embodiment, the finger is vibrated to render the probe spacing insensitive; and in a forth embodiment the microdeflector unit is modified to function as the image reading device in a multi-code copier/printer application.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.