Coordinate input device and input display apparatus including the input device

• US 5,867,151 A
• Filed: 03/25/1997
• Issued: 02/02/1999
• Est. Priority Date: 03/25/1996
• Status: Expired due to Term

• Current Assignee: Japan Display Central Incorporated (Japan Display Incorporated)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Nakai, Yutaka
• Primary Examiner(s): Mengistu, Amare
• Assistant Examiner(s): Osorio, Ricardo
• Application Number:
  US08/824,090
• Time in Patent Office: 679 Days
• Field of Search: 345/173, 345/174, 345/175, 345/176, 345/178, 178/18.01, 178/18.03
• US Class Current: 345/173
• CPC Class Codes: G06F 3/041 Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/04146 using pressure sensitive conductive elements delivering a boolean signal and located between crossing sensing lines, e.g. located between X and Y sensing line layers

Abstract

On a transparent substrate of a coordinate input device are formed a plurality of first wirings formed on a light transmitting substrate to extend in parallel in a first direction, and a plurality of second wirings extending in a second direction perpendicular to the first direction. Each of the second wirings is removed at the intersection with the first wiring to form intermittent divided sections. A flexible electrode is also formed on the substrate to bring two adjacent divided sections of the second wiring into an electrical contact with each other, and faces the first wiring located between the divided section, with a free space defined therebetween. When an external pressure is applied toward the first wiring, the flexible electrode, which is connected to the second wiring, is deformed so as to be brought into an electrical contact with the corresponding first electrode. The light transmitting substrate is arranged to face a counter substrate of a liquid crystal display device.

Claims

1. A coordinate input device comprising:

a plurality of first wirings formed on a substrate to extend in parallel in a first direction;

a plurality of second wirings formed on the substrate to extend in parallel in a second direction perpendicular to the first direction, the intersections of the second wirings with the first wirings being removed to form intermittent divided sections; and

a plurality of flexible electrodes each of which is bridged between two adjacent divided sections of each second wiring to electrically connect the divided sections each other and faces the first wiring located between the two adjacent divided sections, with a free space defined therebetween, the flexible electrode being deformable upon receipt of an external pressure applied from outside toward the first wiring so as to be brought into an electrical contact with the first wiring.

2. A coordinate input device according to claim 1, wherein the substrate is made of a light transmitting material, and at least one of the first wiring, second wiring and flexible electrode is made of a light transmitting material.

3. A coordinate input device according to claim 1, further comprising:

means for applying a voltage to one end of each first wiring through a resistance electrode; and

arithmetic means connected to the other end of each first wiring through another resistance electrode and to both ends of each second wiring through additional resistance electrodes, for detecting the coordinates of the flexible electrode electrically connected to the corresponding first wiring upon receipt of an external pressure, based on the currents supplied through the resistance electrodes.

4. A coordinate input device according to claim 1, further comprising:

a first scanning circuit including a plurality of first switches connected to one ends of the first wirings, the first switches being capable of being closed and opened successively;

a second scanning circuit including a plurality of second switches connected to one ends of the second wirings, the second switches being capable of being closed and opened successively;

means for applying a voltage to the second wirings through the second scanning circuit; and

arithmetic means connected to the first wirings through the first scanning circuit, for detecting the coordinates of the flexible electrode electrically connected to the corresponding first wiring upon receipt of an external pressure, on the basis of the current supplied to the arithmetic means through the first scanning circuit.

5. A coordinate input device according to claim 1, further comprising:

a protective layer formed on the substrate to cover the first and second wirings and the flexible electrodes.

6. An input display apparatus comprising:

a display device; and

a coordinate input device arranged to face a display plane of the display device;

the coordinate input device including;

a plurality of first wirings formed on a substrate to extend in parallel in a first direction;

a plurality of second wirings formed on the substrate to extend in parallel in a second direction perpendicular to the first direction, the intersections of the second wirings with the first wirings being removed to form intermittent divided sections; and

a plurality of flexible electrodes each of which is bridged between two adjacent divided sections of each second wiring to electrically connect the divided sections each other and faces the first wiring located between the two adjacent divided section, with a free space defined therebetween, the flexible electrode being deformable upon receipt of an external pressure applied from outside toward the first wiring so as to be brought into an electrical contact with the first wiring.

7. An input display apparatus according to claim 6, wherein at least one of the first and second wirings and flexible electrode is formed of a light transmitting material.

8. An input display apparatus according to claim 6, wherein the display device includes a plurality of pixels forming an image, and the first and second wirings and flexible electrodes included in the coordinate input device are arranged to face the peripheral portions of the pixels of the display device.

9. An input display device according to claim 6, wherein the display device includes a light transmitting substrate which constitutes the display plane and the substrate of the coordinate input device.

10. An input display apparatus according to claim 6, further comprising:

means for applying a voltage to one end of each first wiring through a resistance electrode; and

arithmetic means connected to the other end of each first wiring through another resistance electrode and to both ends of each second wiring through additional resistance electrodes, for detecting the coordinates of the flexible electrode electrically connected to the corresponding first wiring upon receipt of an external pressure based on the currents supplied through the resistance electrodes.

11. An input display apparatus according to claim 6, further comprising:

a first scanning circuit including a plurality of first switches connected to respective one ends of the first wirings, the first switches being capable of being closed and opened successively;

a second scanning circuit including a plurality of second switches connected to respective one ends of the second wirings, the second switches being capable of being closed and opened successively;

means for applying a voltage to the second wirings through the second scanning circuit; and

arithmetic means connected to the first wirings through the first scanning circuit, for detecting the coordinates of the flexible electrode electrically connected to the corresponding first wiring upon receipt of the external pressure, on the basis of the current supplied to the arithmetic means through the first scanning circuit.

12. An input display device according to claim 6, further comprising:

a protective layer formed on the substrate to cover the first and second wirings and the flexible electrodes,

wherein the substrate of the coordinate input device is formed of a flexible material, and the coordinate input device is arranged such that the protective layer is positioned to face the display plane of the display device.

13. An input display device according to claim 6, wherein the display device includes an array substrate having a plurality of pixel electrodes formed thereon;

a counter substrate having a light shielding layer positioned to face the peripheral portion of each of the pixel electrodes, and a counter electrode formed thereon; and

a liquid crystal layer sealed between the array substrate and the counter substrate, and

the coordinate input device is arranged to face the counter substrate of the display device such that the first and second wirings and the flexible electrodes are overlapped with the light shielding layer of the display device.