TOUCH PANEL AND DISPLAY DEVICE INCLUDING THE SAME

• US 20130093721A1
• Filed: 09/14/2012
• Published: 04/18/2013
• Est. Priority Date: 10/12/2011
• Status: Active Grant

• Current Assignee: Trivale Technologies, LLC (Vector Capital Corporation)
• Original Assignee: Mitsubishi Electric Corporation
• Inventors: MIYAYAMA, Takashi, NAKAMURA, Tatsuya, MORI, Seiichiro
• Granted Patent: US 9,170,689 B2
• Time in Patent Office: Days
• US Class Current: 345/174
• CPC Class Codes: G06F 2203/04103 Manufacturing, i.e. details related to manufacturing processes specially suited for touch sensitive devices
• CPC Class Codes: G06F 3/041 Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• 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

A touch screen of a touch panel includes plural detection column wirings and plural detection row wirings that cross the detection column wirings. Dummy column wirings having a similar configuration to that of the detection column wirings are arrayed at further outer sides of outermost detection column wirings out of the plural detection column wirings. Dummy row wirings having a similar configuration to that of the detection row wirings are arrayed at further outer sides of outermost detection row wirings out of the plural detection row wirings.

Claims

1. A touch panel comprising:

a touch screen including a plurality of detection wirings arrayed in parallel; and

parasitic capacitance setting means that sets parasitic capacitances of an outermost detection wiring out of said plurality of detection wirings equivalent to parasitic capacitances of other detection wirings.

2. The touch panel according to claim 1, wherein

said parasitic capacitance setting means includes one or more dummy wirings arrayed at further outer side of said outermost detection wiring, in parallel with said outermost detection wirings

3. The touch panel according to claim 2, wherein

shapes and widths of said dummy wirings are the same as those of said plurality of detection wirings, and

an interval between one of said dummy wirings and said outermost detection wiring is the same as an interval between said plurality of detection wirings.

4. The touch panel according to claim 2, wherein

a plurality of said dummy wirings are arrayed at further outer side of said outermost detection wiring.

5. The touch panel according to claim 2, wherein

each of said plurality of detection wirings and said dummy wirings is made of a bundle of a plurality of metal thin lines.

6. The touch panel according to claim 2, wherein

each of said plurality of detection wirings and said dummy wirings is formed of a transparent conductive material.

7. The touch panel according to claim 1, wherein

said parasitic capacitance setting means is said outermost detection wiring, and

a width of said outermost detection wiring is formed smaller than those of other detection wirings.

8. The touch panel according to claim 1, comprising a plurality of detection column wirings extended to a column direction and a plurality of detection row wirings extended to a row direction, as said plurality of detection wirings.

9. The touch panel according to claim 8, further comprising:

a switch circuit that sequentially selects said plurality of detection column wirings and said plurality of detection row wirings;

an oscillation circuit that oscillates in a cycle corresponding to a capacitance component of said detection wiring selected by said switch circuit; and

a coordinate calculating circuit that calculates coordinates of an indicator which touches said touch screen, based on a change of an oscillation cycle of said oscillation circuit.

10. A display device comprising a display panel having said touch screen of the touch panel according to claim 9 arrayed on a front surface.

11. The display device according to claim 10, wherein said touch screen of said touch panel is adhered to a front surface of said display panel.