Touch panel device
US7230612B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 29, 2003 |
| Grant date | Jun 12, 2007 |
| Priority date | — |
| Expiry date | Dec 22, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F3/0436
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Surface acoustic waves are propagated in a lower-left oblique direction and a lower-right oblique direction from an excitation element located on the upper side of a non-piezoelectric substrate and then received by receiving elements located on the left side and the right side, while surface acoustic waves are propagated in an upper-left oblique direction and an upper-right oblique direction from an excitation element located on the lower side of the non-piezoelectric substrate and then received by the receiving elements located on the left side and the right side. Based on the received results at the two receiving elements, a position of an object in contact with the non-piezoelectric substrate is detected. The sensitivity in a region near the diagonal, which is influenced largely by propagation loss of the surface acoustic waves, is improved by increasing the widths of the electrode fingers of the excitation elements and/or the receiving elements, the number of pairs of the electrode fingers, or the aperture width of comb-like electrodes, according to an increase in the propagation distances of the surface acoustic waves, i.e., toward the region near the diagonal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.