Padless touch sensor
US5760715A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 15, 1997 |
| Grant date | Jun 2, 1998 |
| Priority date | — |
| Expiry date | Apr 15, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K17/9622
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
The padless touch sensor is used for detecting a touch at a sensing location onto a dielectric element by a user coupled to earth. The sensor comprises a conductive plate attached under the dielectric element and in registry with the sensing location. A predetermined potential is applied on the conductive plate. Simultaneously, test pulses are produced into earth. When the user touches the dielectric element at the sensing location, a potential variation in the conductive plate is produced during a test pulse due to a capacitive circuit formed between earth, the user and the sensor. No deposition of conductive pads on the dielectric element or other special processes are required. Foreign matter or objects placed directly on top of the dielectric element will not erroneously produce a touch condition.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.