Capacitance-type measuring device for absolute measurement of positions
US4879508A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 31, 1988 |
| Grant date | Nov 7, 1989 |
| Priority date | — |
| Expiry date | May 31, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01D5/2415
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Capacitive-type measuring apparatus for making absolute measurements comprises first and second support members which are relatively displaceable with respect to a measurement axis; an array of first transmitter electrodes disposed on the first support member; an array of first receiver electrodes disposed on the second support member such that differing portions of the first receiver electrode array are capacitively coupled with the first transmitter electrode array in dependence on the relative positions of the support members; an array of second transmitter electrodes disposed on the second support member so as to be spatially offset from and electrically connected to corresponding first receiver electrodes; and a second receiver electrode arrangement disposed on the first support member for sensing the voltage distribution of the electric field created by the second transmitter electrode array in response to excitation of the first transmitter electrode array with N excitation signals. The degree of offset of a second transmitter electrode relative to its corresponding first receiver electrode is a predetermined function of the distance of the second transmitter electrode from …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.