Systems and methods for sensing position and movement
US4767973A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 6, 1987 |
| Grant date | Aug 30, 1988 |
| Priority date | — |
| Expiry date | Jul 6, 2007 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R23/006
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Sensor systems and methods for detecting the position and/or movement of an object in multiple degrees of freedom. The sensor system of the present invention comprises at least one field-effect transistor (FET), the geometrical configuration of the FET being selected so as to provide the desired sensitivity. The FET is preferably provided with a conductive gate adjacent to but insulated from the channel region of the FET. An object whose position and/or movement is to be detected is prepared such that an electric field emanates from the object. The FET is brought into the vicinity of the object, and the electric field emanating from the object interacts with the gate and/or channel region of the FET so as to modify the magnitude of the electrical current flowing through the channel region. The current through the channel region is detected and is used to obtain information about the position and movement of the object relative to the channel region of the FET. By positioning a plurality of substantially coplanar FETs in the vicinity of the object, the position and/or movement of the object in any desired number of degrees of freedom can be detected and monitored.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.