Electrostatic capacitance-type input device, method of testing electrostatic capacitance-type input device, and driving device for electrostatic capacitance-type input device

• US 8,598,896 B2
• Filed: 12/07/2010
• Issued: 12/03/2013
• Est. Priority Date: 12/15/2009
• Status: Active Grant

• Current Assignee: Japan Display West Incorporated (Japan Display Incorporated)
• Original Assignee: Japan Display West Incorporated (Japan Display Incorporated)
• Inventors: Kurashima, Takeshi
• Primary Examiner(s): NATALINI, JEFF WILLIAM
• Application Number:
  US12/961,843
• Publication Number:
  US 20110140720A1
• Time in Patent Office: 1,092 Days
• Field of Search: 324/686
• US Class Current: 324/686
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes
• 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

An electrostatic capacitance-type input device includes: a plurality of first electrodes, which detect an input position, extending in a first direction in an input area on a substrate; a plurality of second electrodes, which detect an input POSITION, extending in a second direction intersecting with the first direction in the input area; a plurality of signal wirings that extend from one-side end portions of the first electrodes and one-side end portions of the second electrodes on the substrate; a test electrode that faces the other-side end portions of at least one of the first electrodes and the second electrodes through an insulating film on the substrate; and a test wiring that is electrically connected to the test electrode.

Claims

1. An electrostatic capacitance-type input device comprising:

a plurality of first electrodes, which detect an input position, extending in a first direction in an input area on a substrate;

a plurality of second electrodes, which detect an input position, extending in a second direction intersecting with the first direction in the input area;

a plurality of signal wirings that extend from one-side end portions of the first electrodes and one-side end portions of the second electrodes on the substrate;

a test electrode that faces, and is capacitively coupled with, the other-side end portions of at least one of the first electrodes and the second electrodes through an insulating film on the substrate;

a test wiring that is electrically connected to the test electrode; and

a short-circuit testing unit that is electrically connected to the test wiring and the plurality of signal wirings,

wherein the short-circuit testing unit measures capacitance values between the test wiring and the plurality of signal wirings and determines that the electrode out of the first electrodes and the second electrodes, which has a capacitance value equal to or less than a set value, and to which the signal wirings are electrically connected is short-circuited.

2. The electrostatic capacitance-type input device according to claim 1, wherein the test electrode overlaps the other-side end portions in a thickness direction through the insulating film so as to face the other-side end portions.

3. The electrostatic capacitance-type input device according to claim 2, further comprising:

a relay electrode that electrically connects the second electrodes disconnected in intersection portions to each other on the substrate,

wherein the second electrodes are disconnected in the intersection portions with the first electrodes, and

wherein the test electrode is disposed at least in the other-side end portion of the second electrodes.

4. The electrostatic capacitance-type input device according to claim 2, wherein the test electrode is disposed in the other-side end portions of the first electrodes and the other-side end portions of the second electrodes.

5. The electrostatic capacitance-type input device according to claim 1,

wherein the test electrode includes a plurality of test electrodes that are independently disposed for each of the other-side end portions, and

wherein the test wiring is electrically connected to a plurality of the test electrodes.

6. The electrostatic capacitance-type input device according to claim 5, wherein the test wiring is electrically connected to all the test electrodes.

7. The electrostatic capacitance-type input device according to claim 1, wherein the test wiring extends so as to surround at least three sides of the input area.

8. A method of testing an electrostatic capacitance-type input device including a plurality of first electrodes, which detect an input position, extending in a first direction in an input area on a substrate, a plurality of second electrodes, which detect an input position, extending in a second direction intersecting with the first direction in the input area;

and a plurality of signal wirings that extend from one-side end portions of the first electrodes and one-side end portions of the second electrode,

wherein a test electrode that faces, and is capacitively coupled with, the other-side end portions of at least one of the first electrodes and the second electrodes through an insulating film and a test wiring that is electrically connected to the test electrode are disposed,

the method comprising the steps of;

measuring capacitance values between the test wiring and the plurality of signal wirings; and

determining that the electrode out of the first electrodes and the second electrodes, which has a capacitance value equal to or less than a set value, and to which the signal wirings are electrically connected is short-circuited.

9. A driving device for an electrostatic capacitance-type input device including a plurality of first electrodes, which detect an input position, extending in a first direction in an input area on a substrate, a plurality of second electrodes, which detect an input position, extending in a second direction intersecting with the first direction in the input area;

and a plurality of signal wirings that extend from one-side end portions of the first electrodes and one-side end portions of the second electrode, the driving device comprising;

a plurality of signal terminals that output position detecting signals to the signal wirings;

a driving unit that supplies position detecting signals to the signal terminals;

a test terminal that is capacitively coupled with the plurality of signal terminals;

a capacitance measuring unit that measures capacitance values between the test terminal and the plurality of signal terminals; and

a short-circuit determining unit that determines whether or not there is the signal terminal having a capacitance value equal to or less than a set value based on a capacitance measuring result of the capacitance measuring unit.