Display device equipped with touch panel

• US 8,922,522 B2
• Filed: 09/22/2011
• Issued: 12/30/2014
• Est. Priority Date: 09/30/2010
• Status: Active Grant

• Current Assignee: Panasonic Intellectual Property Corporation of America (Panasonic Holdings Corporation)
• Original Assignee: Japan Display Incorporated, Panasonic Liquid Crystal Display Company Limited (Panasonic Holdings Corporation)
• Inventors: Atsuta, Toshiaki, Nagata, Koji, Doi, Koji
• Primary Examiner(s): Sitta, Grant
• Application Number:
  US13/239,845
• Publication Number:
  US 20120081332A1
• Time in Patent Office: 1,195 Days
• Field of Search: 345173-176, 345/51, 345 87- 93
• US Class Current: 345/174
• CPC Class Codes: G06F 3/0418 for error correction or compensation, e.g. based on parallax, calibration or alignment
• CPC Class Codes: G06F 3/0445 using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer
• CPC Class Codes: G06F 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes

Abstract

Provided is a display device equipped with a touch panel, including a front panel arranged above a capacitive touch panel at a predetermined distance away therefrom, in which the touch panel includes a plurality of X electrodes and a plurality of Y electrodes, and the X electrodes are sequentially applied with pulse signals and the Y electrodes receive the pulse signals. When an arbitrary point on the front panel is touched, the touch panel computes a touched point on the touch panel by using both the received pulse signals obtained from the Y electrodes in a case where the front panel is not deformed and the received pulse signals obtained from the Y electrodes in a case where the front panel is deformed. With this, an erroneous operation in which a measurement value is lowered to finally disappear is prevented.

Claims

1. A touch panel, comprising:

a capacitive touch panel; and

a front panel arranged above the capacitive touch panel at a predetermined distance away therefrom to allow for deformation of the front panel toward the capacitive touch panel in response to a touch force exceeding a predetermined amount, wherein;

the capacitive touch panel includes a plurality of X electrodes and a plurality of Y electrodes,

the X electrodes being sequentially applied with pulse signals, and the Y electrodes receiving pulse signals;

when an arbitrary point on the front panel is touched, a same touched point on the capacitive touch panel is computed by using the received signals including both a first signal obtained from the Y electrodes in a case where the front panel is not deformed and a second signal obtained from the Y electrodes in a case where the front panel is deformed; and

polarities of the first signal and the second signal are opposite to each other relative to a reference value, and

the first signal shifts toward a first side from the reference value, and

the second signal shifts towards a second side from the first side across the reference value in succession to the first signal.

9. The display device equipped with a touch panel according to claim 1, wherein the front panel is arranged above the capacitive touch panel at the predetermined distance away therefrom by a spacer provided in a peripheral portion of the capacitive touch panel.

10. The display device equipped with a touch panel according to claim 1, wherein the X electrodes and the Y electrodes cross each other via a first insulating layer, each of the X electrodes and the Y electrodes has a pad portion and a thin-line portion that are formed to be alternately arranged in each electrode-extending direction, and the pad portions of the X electrodes and the pad portions of the Y electrodes are arranged without overlapping each other as viewed planarly.

11. The display device equipped with a touch panel according to claim 1, wherein the X electrodes and the Y electrodes cross each other at the intersections via a first insulating layer, each of the X electrodes and the Y electrodes has a pad portion and a thin-line portion that are formed to be alternately arranged in each electrode-extending direction, and the pad portions of the X electrodes and the pad portions of the Y electrodes are arranged without overlapping each other as viewed planarly.

2. A touch panel, comprising:

a capacitive touch panel provided; and

a front panel arranged above the capacitive touch panel at a predetermined distance therefrom to allow for deformation of the front panel toward the capacitive touch panel in response to a touch force exceeding a predetermined amount,

wherein the capacitive touch panel includes;

a plurality of X electrodes; and

a plurality of Y electrodes;

a measurement unit for sequentially applying pulse signals to one electrode of the X electrodes and the Y electrodes and receiving the pulse signals from another one electrode of the X electrodes and the Y electrodes so as to measure intensity of each of the received pulse signals; and

a control unit for detecting an intersection at which the measured intensity of the received pulse signal is larger than a first threshold value and an intersection at which the measured intensity of the received pulse signal is smaller than a second threshold value among intersections of the plurality of X electrodes and the plurality of Y electrodes so as to compute a touched position on the capacitive touch panel, and

the measured intensity shifts toward a first threshold value from a reference value when a first load is applied on the front panel, and shifts in an opposite direction towards a second threshold value from the first threshold value across the reference value when a second load, which is larger than the first load, is applied to the front panel.

3. The display device equipped with a touch panel according to claim 2, wherein:

the measured intensity of the received pulse signal becomes larger than the first threshold value when the front panel is touched so that the front panel is not deformed;

the measured intensity of the received pulse signal becomes smaller than the second threshold value when the front panel is touched so that the front panel is deformed toward the capacitive touch panel; and

the first threshold value is larger than the second threshold value.

4. The display device equipped with a touch panel according to claim 3, wherein:

the first threshold value is set on a side on which the intensity of the received pulse signal increases from a reference value; and

the second threshold value is set on a side on which the intensity of the received pulse signal decreases from the reference value.

5. The display device equipped with a touch panel according to claim 4, wherein the reference value is set based on a state in which the capacitive touch panel is not touched.

6. The display device equipped with a touch panel according to claim 4, further comprising a storage unit for storing the measured intensity of the received pulse signal and the reference value for each of the intersections of the X electrodes and the Y electrodes.

7. The display device equipped with a touch panel according to claim 6, wherein the storage unit stores a touch-state management table for managing the touched position.

8. The display device equipped with a touch panel according to claim 2, wherein the control unit reverses polarity of the measured received pulse signal when the measured intensity of the received pulse signal is smaller than the second threshold value.

12. The touch panel according to claim 2, wherein the measured intensity shifting toward the first threshold value and the measured intensity value shifting toward to the second threshold value are measured at the same intersection.