Capacitive systems for touch control switching
US4380040A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 7, 1980 |
| Grant date | Apr 12, 1983 |
| Priority date | — |
| Expiry date | Aug 7, 2000 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K17/962
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
In capacitive systems comprising a dielectric sheet 11 having a first electrode 12 on one side, and on the other side in capacitive relation with the first electrode 12, second and third electrodes 13, 14 which are mutually spaced by a gap 15 especially for use in touch control switches, it is desired to achieve a favorable compromise between high capacitance modification as between touched and untouched condition of the first electrode 12, and the total amount of material used to form the electrodes. To this end, the third or outer electrode 14 is shaped to surround at least the major part of the periphery of the second or inner electrode 13, and the ratio of the area of the inner electrode 13 to the area of the outer electrode 14 is greater than 0.25 to 1.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.