DISPLAY DEVICE

• US 20110157064A1
• Filed: 08/20/2009
• Published: 06/30/2011
• Est. Priority Date: 08/25/2008
• Status: Abandoned Application

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Imai, Masahiro
• Application Number:
  US13/060,629
• Publication Number:
  US 20110157064A1
• Time in Patent Office: Days
• US Class Current: 345/173
• CPC Class Codes: G06F 3/0416 Control or interface arrangements specially adapted for digitisers
• CPC Class Codes: G09G 2330/06 Handling electromagnetic interferences [EMI], covering emitted as well as received electromagnetic radiation
• CPC Class Codes: G09G 3/3611 Control of matrices with row and column drivers

Abstract

Provided is a display device that, even if noise has been generated due to a signal for image display being applied to a display unit, can acquire correct position information free of the influence of noise from a touch panel unit. The display device includes a display unit having a plurality of electrodes for image display, a display control unit (22) that controls image display performed by the display unit by applying, to the electrodes of the display unit, electrode driving signals whose voltage levels change with a predetermined cycle, a touch panel unit that detects an input position from the outside, and a touch panel control unit (21) that acquires a position detection signal by applying a scan signal to the touch panel unit. The touch panel control unit (21) applies the scan signal three or more times in a cycle in which the voltage levels of the electrode driving signals change and compares the obtained position detection signals corresponding to the scan signals, determines position information indicated by two or more of the position detection signals that indicate the same result as being correct position information, and outputs the determined position information as a position signal.

Claims

1. A display device comprising:

a display unit having a plurality of electrodes for image display;

a display control unit that controls image display performed by the display unit by applying, to the plurality of electrodes of the display unit, electrode driving signals whose voltage levels change with a predetermined cycle;

a touch panel unit that detects an input position from the outside; and

a touch panel control unit that acquires a position detection signal by applying a scan signal to the touch panel unit,

wherein the touch panel control unit applies the scan signal three or more times in a cycle in which the voltage levels of the electrode driving signals change and compares the obtained position detection signals corresponding to the scan signals, determines position information indicated by two or more of the position detection signals that indicate the same result as being correct position information, and outputs the determined position information as a position signal.

2. The display device according to claim 1,

wherein the display control unit causes timings of change in the voltage levels of the electrode driving signals applied to the plurality of electrodes of the display unit to be the same timing.

3. The display device according to claim 1,

wherein the display device has a display panel in which the display unit that performs image display is formed, and a touch panel in which the touch panel unit that detects input information is formed, and

the touch panel is arranged adjacent to a display face of the display panel.

4. The display device according to claim 1,

wherein the display unit is a liquid crystal panel in which a liquid crystal layer is sandwiched between two opposing substrates.