TOUCH PANEL HAVING PRESS DETECTION FUNCTION AND PRESSURE SENSITIVE SENSOR FOR THE TOUCH PANEL

• US 20110115738A1
• Filed: 12/24/2009
• Published: 05/19/2011
• Est. Priority Date: 12/25/2008
• Status: Active Grant

• Current Assignee: Nissha Printing Company Limited
• Original Assignee: Nissha Printing Company Limited
• Inventors: Suzuki, Takahiro, Shimizu, Jun, Okumura, Shuzo, Hirai, Seiko, Yamaoka, Yoshitaka, Endo, Yuko, Imai, Yohko, Takai, Yuichiro, Kai, Yoshihiro
• Granted Patent: US 8,094,134 B2
• Time in Patent Office: Days
• US Class Current: 345/173
• CPC Class Codes: G01L 1/205 using distributed sensing elements
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• CPC Class Codes: G06F 2203/04105 Pressure sensors for measuring the pressure or force exerted on the touch surface without providing the touch position
• 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
• CPC Class Codes: G06F 3/0447 Position sensing using the local deformation of sensor cells
• CPC Class Codes: G06F 3/045 using resistive elements, e.g. a single continuous surface or two parallel surfaces put in contact

Abstract

An object of the present invention is to provide a touch panel having a press detection function, which makes it possible to suppress degradation of visibility of a display unit of a display device even when mounted on an electronic device, and also to improve a pressure measuring precision. For this purpose, the touch panel of the present invention includes a first substrate, a second substrate disposed oppose to the first substrate, a pair of electrodes disposed on either one of opposed surfaces of the respective substrates or disposed separately on both of the surfaces, pressure sensitive ink members disposed with a gap from at least one of the pair of electrodes, each of the pressure sensitive ink members having an electrical characteristic varied by a pressing force applied thereto, and a gap retaining member for bonding the first and second substrates to each other and for retaining a gap between each of the pressure sensitive inks and at least one of the pair of electrodes, wherein the pair of electrodes are disposed in a frame shape along an edge portion of the first or second substrate, and the pressure sensitive ink members are scattered along the edge portion of the first or second substrate so that, when the first or second substrate is deformed upon an application of an external force, at least one of them is made in contact with both of the pair of electrodes so as to make the two electrodes conductive to each other.

Claims

1. A touch panel provided with a press detection function, the touch panel comprising a pressure sensitive sensor for the touch panel, wherein

the pressure sensitive sensor for the touch panel includes:

a first substrate;

a second substrate disposed so as to be opposed to the first substrate;

a pair of electrodes disposed on either one of a surface of the first substrate opposed to the second substrate and a surface of the second substrate opposed to the first substrate, or disposed separately on both of the surfaces;

pressure sensitive ink members having conductive property of which electric characteristic is varied by a pressing force applied thereto, each of the pressure sensitive ink members being disposed on the surface of the first substrate opposed to the second substrate or the surface of the second substrate opposed to the first substrate with a gap interposed from at least one of the pair of electrodes; and

a gap retaining member disposed on an opposed area between the first substrate and the second substrate, the gap retaining member having such sticking property that the first substrate and the second substrate are bonded to each other and retaining the gap between each of the pressure sensitive ink members and at least one of the pair of electrodes,

the pair of electrodes are disposed in a frame shape along an edge portion of the first or second substrate,

the pressure sensitive ink members are located in a scattered manner along the edge portion of the first or second substrate, and when, upon application of an external force in a thickness direction of the first substrate, the first or second substrate is deformed, the pressure sensitive ink member is made in contact with both of the pair of electrodes so that the pair of electrodes are made conductive to each other.

2. The touch panel provided with a press detection function according to claim 1, wherein the gap retaining member is a double-sided sticky tape with a sticky agent being applied onto two surfaces of a core member.

3. The touch panel provided with a press detection function according to claim 1, wherein the pressure sensitive ink members are provided as dots disposed on a plurality of corners of the first substrate or the second substrate.

4. The touch panel provided with a press detection function according to claim 1, wherein each of the first substrate and the second substrate has a rectangular outer shape, and

the pressure sensitive ink members are provided in a broken line shape along only each of edge portions of paired longer sides of the first substrate or the second substrate.

5. The touch panel provided with a press detection function according to claim 1, wherein the pressure sensitive ink members are disposed at a pitch in a range of from 9.75 mm to 25.75 mm.

6. The touch panel provided with a press detection function according to claim 1, wherein each of the first substrate, the second substrate, and the gap retaining member is formed into a frame shape.

7. The touch panel provided with a press detection function according to claim 1, wherein each of the first substrate and the second substrate is made of a transparent material so as to have a flat plate shape, with a transparent window portion being formed on a portion without the pair of electrodes formed therein.

8. The touch panel provided with a press detection function according to claim 7, wherein a transparent electromagnetic shielding member is disposed on the first substrate or the second substrate so as to include the transparent window portion.

9. The touch panel provided with a press detection function according to claim 7, wherein the second substrate has a transparent electrode formed on the transparent window portion of the surface opposed to the first substrate into a stripe pattern in one direction.

10. The touch panel provided with a press detection function according to claim 9, wherein a third substrate is stacked on a surface of the second substrate on a side without the pair of electrodes formed thereon, with an sticky agent interposed therebetween, and

the third substrate is made of a transparent material so as to have a flat plate shape, and is provided with a transparent electrode formed on an area corresponding to the transparent window portion of the surface opposed to the second substrate into a stripe pattern in a direction crossing the one direction.

11. The touch panel provided with a press detection function according to claim 1, further comprising:

a supporting member stacked and disposed on at least one of surfaces of the first substrate and the second substrate on a side without the pair of electrodes formed thereon.

12. The touch panel provided with a press detection function according to claim 11, wherein the supporting member is provided on a rear side of a position where the pressure sensitive ink member is formed.

13. The touch panel provided with a press detection function according to claim 1, wherein

one of the pair of electrodes is disposed on the first substrate,

an other one of the pair of electrodes is disposed on the second substrate, and

the pressure sensitive ink members are provided to cover a plurality of portions of the one or the other one of the pair of electrodes.

14. The touch panel provided with a press detection function according to claim 13, wherein the pair of electrodes are covered with either one of the pressure sensitive ink member or the gap retaining member.

15. The touch panel provided with a press detection function according to claim 1, wherein

the pair of electrodes are disposed on the first substrate with a gap therebetween, and

the pressure sensitive ink members are disposed on the second substrate.

16. A pressure sensitive sensor for a touch panel comprising:

a first substrate;

a second substrate disposed so as to be opposed to the first substrate;

a pair of electrodes disposed on either one of a surface of the first substrate opposed to the second substrate and a surface of the second substrate opposed to the first substrate, or disposed separately on both of the surfaces;

pressure sensitive ink members having conductive property of which electric characteristic is varied by a pressing force applied thereto, each of the pressure sensitive ink members being disposed on the surface of the first substrate opposed to the second substrate or the surface of the second substrate opposed to the first substrate with a gap interposed from at least one of the pair of electrodes; and

a gap retaining member disposed on an opposed area between the first substrate and the second substrate, the gap retaining member having such sticking property that the first substrate and the second substrate are bonded to each other and retaining the gap between each of the pressure sensitive ink members and at least one of the pair of electrodes, wherein

the pair of electrodes are disposed in a frame shape along an edge portion of the first or second substrate,

the pressure sensitive ink members are located in a scattered manner along the edge portion of the first or second substrate, and when, upon application of an external force in a thickness direction of the first substrate, the first or second substrate is deformed, the pressure sensitive ink member is made in contact with both of the pair of electrodes so that the pair of electrodes are made conductive to each other.