Display system

• US 7,683,887 B2
• Filed: 09/22/2004
• Issued: 03/23/2010
• Est. Priority Date: 11/28/2003
• Status: Expired due to Fees

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Yasukawa, Sadahiko
• Primary Examiner(s): Mengistu; Amare
• Assistant Examiner(s): PATEL, PREMAL R
• Application Number:
  US10/596,063
• Publication Number:
  US 20090015562A1
• Time in Patent Office: 2,008 Days
• Field of Search: 345/87, 345/173, 345/174, 345/204, 178 1801- 1808
• US Class Current: 345/173
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/045 using resistive elements, e.g. a single continuous surface or two parallel surfaces put in contact

Abstract

A touch-panel-integrated liquid crystal display device (display system) includes a liquid crystal display device, and a touch panel input device, provided on a liquid crystal panel of the liquid crystal display device, which has upper and lower electrodes (conductive thin plates) for detecting a position via which information is inputted from the outside. The display system includes a liquid crystal display device driving section for driving the liquid crystal display device and a noise canceling signal generator (signal application section) for applying, to the touch panel input device, a noise canceling signal having an amplitude and a phase that are equal to an amplitude and a phase of a driving signal applied from the liquid crystal display device driving section to the liquid crystal panel.

Claims

1. A display system, which includes a display device and an input device, the input device being provided on a display section of the display device and having one or more conductive thin plates and being arranged to detect a position via which information is inputted from outside, said display system comprising:

a display device driving section arranged to drive the display device;

a signal application section arranged to apply, to the device having the one or more conductive thin plates, a noise canceling signal having an amplitude and a phase that are equal with an amplitude and a phase of a driving signal applied from the display device driving section to the display device;

an input device control section to which a detection signal is applied, the detection signal being arranged to detect a position via which information is inputted from outside to the conductive thin plate; and

a signal switching section arranged to select either the noise canceling signal or the detection signal so as to input the selected signal to the conductive thin plate.

2. The display system according to claim 1, wherein the device having the one or more conductive thin plates includes two conductive thin plates overlapping each other, and the noise canceling signal is applied to at least a conductive thin plate of the two conductive thin plates which is located closer to the display section of the display device.

3. The display system according to claim 1, wherein the input device has two conductive thin films overlapping each other, and the noise canceling signal is applied to at least a conductive thin plate of the two conductive thin plates which is located closer to the display section of the display device.

4. The display system according to claim 1, wherein the signal switching section switches the noise canceling signal to the detection signal or switches the detection signal to the noise canceling signal in accordance with whether or not information is inputted from outside to the conductive thin plate.

5. The display system according to claim 1, wherein in a case where the display system is provided on a device having at least one of a telephone function and a sound collecting function, the signal switching section selects the noise canceling signal in using said at least one of the telephone function and the sound collecting function so as to input the noise canceling signal to the conductive thin plate.

6. The display system according to claim 1, wherein the input device further includes a conversion circuit arranged to convert an amplitude of the noise canceling signal before inputting the noise canceling signal to the input device control section.

7. The display system according to claim 1, wherein the display section of the display device is a liquid crystal panel which has two substrates and liquid crystal provided between the two substrates, and the noise canceling signal has an amplitude and a phase that are equal to an amplitude and a phase of a driving signal which influences electric charge existing between the liquid crystal panel and the one or more conductive thin plates.

8. The display system according to claim 1, wherein the display section of the display device is a liquid crystal panel which has two substrates and liquid crystal provided between the two substrates, a thin film transistor is provided on a substrate of the two substrates which is positioned further from the one or more conductive thin plates, and the noise canceling signal has an amplitude and a phase that are equal to an amplitude and a phase of a driving signal applied to a substrate of the two substrates which is positioned closer to the one or more conductive thin plates.