Method and apparatus for detecting defective traces in a mutual capacitance touch sensing device
US8279197B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 25, 2009 |
| Grant date | Oct 2, 2012 |
| Priority date | — |
| Expiry date | Dec 31, 2030 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F11/2221
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Several different methods of testing the integrity and proper operation of the drive and sense electrodes in a mutual capacitance sensing device such as a touchscreen or touchpad are disclosed herein. According to one embodiment, measured values of mutual capacitance corresponding to individual cells in a mutual capacitance sensing device are compared to one another and to predetermined thresholds. The results of the comparison are employed to determine whether any of the traces forming the electrodes in the device are defective. By way of example, traces can be defective if they are broken, too thin, too thick, or shorted together. The various embodiments of the methods disclosed herein may be used for touchscreen or touchpad quality control in a manufacturing setting, or may be used to test touchscreens or touchpads that have already been incorporated into electronic devices. The various methods disclosed herein lower manufacturing costs, increase product quality and yield, and may be carried out quickly.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.