Light sensing circuit, method of driving the same, and touch panel including the light sensing circuit
US8289298B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 29, 2009 |
| Grant date | Oct 16, 2012 |
| Priority date | — |
| Expiry date | Dec 19, 2030 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F3/042
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A light sensing circuit, a method of driving the same, and a touch panel including the light sensing circuit, the light sensing circuit including a photodiode generating current according to the brightness of light incident from the outside; a driving transistor having a first electrode to which a first power voltage is applied, a second electrode, and a gate electrode electrically connected to a cathode of the photodiode; a first reset transistor having a first electrode to which an initialization voltage is applied, a second electrode connected to the gate electrode of the driving transistor, and a gate electrode to which a previous scan signal is applied; and a shielding capacitor disposed between the gate electrode of the driving transistor and the cathode of the photodiode. Accordingly, the brightness of light incident on the photodiode can be accurately determined by initializing the cathode of the photodiode by using a constant voltage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.