Method of detecting a touch position and touch panel for performing the same

• US 8,378,991 B2
• Filed: 08/13/2008
• Issued: 02/19/2013
• Est. Priority Date: 08/21/2007
• Status: Expired due to Fees

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Inventors: Jeon, Jin, Kim, Hyung-Guel, Uh, Kee-Han
• Primary Examiner(s): CERULLO, LILIANA P
• Application Number:
  US12/191,212
• Publication Number:
  US 20090050376A1
• Time in Patent Office: 1,651 Days
• Field of Search: 345156-184, 340/71, 341/23, 349/12, 178 1803- 2004
• US Class Current: 345/174
• CPC Class Codes: G06F 3/04166 Details of scanning methods, e.g. sampling time, grouping of sub areas or time sharing with display driving Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally G06F3/04184

Abstract

A method of detecting a touch position and a touch panel for performing the method are disclosed. In the above-mentioned method, a plurality of scan signals is sequentially supplied to a plurality of first sensor lines arranged in a first direction. Then, at least one of the scan signals is analyzed based on touch events, which is transferred from the first sensor lines to a plurality of second sensor lines arranged in a second direction substantially across to the first direction, and then at least one of touch positions is detected. Therefore, a plurality of scan signals is sequentially applied to the first sensor lines in the first direction, so that a plurality of touch events is simultaneously detected so that a plurality of touch positions may be detected.

Claims

1. A method of detecting a touch position, the method comprising:

sequentially supplying a plurality of scan signals to a plurality of first sensor lines arranged in a first direction; and

detecting at least one touch position where touch events are generated, by analyzing at least one of the scan signals transferred from the first sensor lines to a plurality of second sensor lines arranged in a second direction substantially crossing the first direction by the touch events,

wherein the detecting at least one touch position comprises turning on of at least one touch switch by the touch event, so that the scan signal is transferred from the first sensor lines to the second sensor lines through the touch switch,

wherein each of the touch switches comprises;

a first sensor electrode formed on a first substrate to be electrically connected to one of the first sensor lines;

a second sensor electrode formed on the first substrate adjacent to the first sensor electrode, the second sensor electrode being electrically connected to one of the second sensor lines; and

a touch electrode formed on a second substrate opposite to the first substrate and the first and second sensor electrodes, the touch electrode being configured to be contacted with the first and second electrodes by the touch event to electrically connect the first and second sensor electrodes such that the scan signal is transferred from the first sensor lines to the second sensor lines;

wherein the touch event is an external force applied from an outside of the panel unit, and when the external force is not applied to the panel, the touch electrode is not contacted with the first and second sensor electrodes;

wherein the touch electrode is electrically isolated from a common electrode, the common electrode formed on the second substrate.

2. The method of claim 1, wherein the detecting at least one touch position further comprises:

storing the scan signal transferred from the second sensor lines in a position detecting memory; and

detecting the at least one touch position by analyzing the data stored in the position detecting memory.

3. The method of claim 2, wherein the detecting the at least one touch position by analyzing the data further comprises distinguishing whether the touch switches is turned on or turned off through the data stored in the position detecting memory, so as to detect the touch position.

4. The method of claim 1, wherein the scan signals are synchronized with a vertical signal for displaying an image.

5. The method of claim 1, wherein the scan signals are synchronized with at least one frequency of about 60 Hz and about 120 Hz.

6. A touch panel comprising:

a panel unit including a plurality of first sensor lines arranged in a first direction and a plurality of second sensor lines arranged in a second direction across to the first direction;

a plurality of sensor switches being disposed in accordance with a plurality of positions where the first and second sensor lines cross each other to electrically connect to the first sensor lines and the second sensor lines; and

a scan signal generating section sequentially supplying a plurality of scan signals to the first sensor lines in the first direction,

wherein each of the sensor switches comprises;

a first sensor electrode formed on a first substrate to be electrically connected to one of the first sensor lines;

a second sensor electrode formed on the first substrate adjacent to the first sensor electrode, the second sensor electrode being electrically connected to one of the second sensor lines; and

a touch electrode formed on a second substrate opposite to the first substrate and the first and second sensor electrodes, the touch electrode being configured to be contacted with the first and second sensor electrodes by an external force to electrically connect the first and second sensor electrodes such that the scan signals are transferred from the first sensor lines to the second sensor lines;

wherein the external force is applied from an outside of the panel unit, and when the external force is not applied to the panel, the touch electrode is not contacted with the first and second sensor electrodes;

wherein the touch electrode is electrically isolated from a common electrode, the common electrode formed on the second substrate.

7. The touch panel of claim 6, wherein the scan signal generating section comprises:

a plurality of scan driving transistors being electrically connected to the first sensor lines, respectively; and

a plurality of scan signal control parts being electrically connected to the scan driving transistors, respectively, to turn on or turn off the scan driving transistors.

8. The touch panel of claim 7, wherein each of the scan driving transistors comprises:

a gate electrode being electrically connected to the scan signal control part to receive a scan control signal from the scan signal control part;

a source electrode receiving a scan voltage; and

a drain electrode being electrically connected to a first terminal of the first sensor line.

9. The touch panel of claim 8, wherein the scan voltage is substantially a ground voltage.

10. The touch panel of claim 6, further comprising a sensor signal output part electrically connected to first terminals of the second sensor lines to output a plurality of sensor signals corresponding to turn-on or turn-off state of the sensor switches.

11. The touch panel of claim 10, further comprising a position detecting memory electrically connected to the sensor signal output part to receive the sensor signals, and storing the sensor signals.

12. The touch panel of claim 11, wherein the position detecting memory comprises a plurality of unit memories storing a data for turn-on or turn-off state of the sensor switches in correspondence with the sensor switches.

13. The touch panel of claim 6, wherein the panel unit comprises:

the first substrate including the first and second sensor lines and a plurality of pixel parts for displaying an image;

the second substrate facing the first substrate; and

a liquid crystal layer interposed between the first and second substrates.

14. The touch panel of claim 6, wherein the common electrode is spaced apart from the touch electrode by a predetermined distance.

15. The touch panel of claim 14, wherein the touch electrode is formed from a conductive layer to form the common electrode.

16. The touch panel of claim 6, wherein each of the sensor switches further comprises a touch spacer formed between the touch electrode and the second substrate to decrease a distance between the touch electrode and the first and second sensor electrodes.

17. The touch panel of claim 13, wherein each of the pixel parts comprises:

a pixel electrode and a thin-film transistor electrically connected to the pixel electrode; and

the first and second sensor electrodes formed from a conductive layer to form the pixel electrode.

18. The touch panel of claim 13, wherein the panel unit further comprises a plurality of cell gap maintaining members disposed in a position adjacent to the sensor switches, respectively, to maintain a cell gap between the first and second substrates.