Touch control system for controllable apparatus
USRE33151E · kind E · reissue
Assignee
Inventor
Key dates
| Filing date | Apr 17, 1989 |
| Grant date | Jan 23, 1990 |
| Priority date | — |
| Expiry date | Apr 17, 2009 |
Classification
- Technology area (CPC —)General
Abstract
A system for recognizing touch positions along an axis on a surface associated with a touch control apparatus comprises a substrate having a surface capable of propagating surface acoustic waves and so characterized that a touch on that surface causes a perturbation of a surface wave passing through the region of touch. An input surface wave transducer coupled to the substrate surface launches a burst of surface waves on the surface. An output surface wave transducer coupled to the substrate detects received surface waves. Wave redirecting gratings derive wave components from the launched wave and redirect them across the substrate surface to the output transducer. The wave components are caused to traverse the axis along a progression of paths associated with different touch positions along the axis. Circuitry coupled to the input and output transducers initiates surface wave bursts across the substrate surface and detects tough-induced perturbations of the received waves indicative of the location of a touch along the axis.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.