Liquid crystal display device

• US 9,766,654 B2
• Filed: 10/08/2009
• Issued: 09/19/2017
• Est. Priority Date: 10/09/2008
• 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: Kuwajima, Yuka, Oohira, Eiji
• Primary Examiner(s): LEE, NICHOLAS J
• Application Number:
  US12/575,508
• Publication Number:
  US 20100090972A1
• Time in Patent Office: 2,903 Days
• Field of Search: 345173-178
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• CPC Class Codes: G06F 1/1626 with a single-body enclosure integrating a flat display, e.g. Personal Digital Assistants [PDAs]
• CPC Class Codes: G06F 1/1637 Details related to the display arrangement, including those related to the mounting of the display in the housing
• CPC Class Codes: G06F 1/1643 the display being associated to a digitizer, e.g. laptops that can be used as penpads details related to the relative motion of the display enclosure with respect to the body enclosure, e.g. to move between laptop and tablet PC configuration G06F1/1615

Abstract

There is disclosed a liquid crystal display device in which a touch panel and a front window are attached to a front surface of a liquid crystal display panel with a touch-panel flexible wiring substrate mounted to the touch panel. The front window is attached to the touch panel by an adhesive sheet. The touch panel and the front window may be peeled off in the vicinity of the portion in which the touch-panel flexible wiring substrate is mounted to the touch panel, due to mechanical shock. In order to prevent the peeling-off of the touch panel and the front window, protrusions are formed in the adhesive sheet to increase the adhesive force between the touch panel and the front window in this portion.

Claims

1. A liquid crystal display device comprising:

a liquid crystal display panel and backlight housed in a resin mold, wherein the liquid crystal display panel having an upper polarization plate on a liquid crystal cell, and the liquid crystal display panel having a display area;

a touch panel attached to the upper polarization plate by a UV curable resin, wherein the touch panel has a display area, and the UV curable resin extends over an entirety of the display area of the liquid crystal display panel; and

a front window attached to the touch panel;

wherein an upper surface of the touch panel and the front window are bonded by an adhesive sheet disposed therebetween;

wherein the adhesive sheet extends over an entirety of the display area of the touch panel at the upper surface of the touch panel;

wherein the front window has a thickness which is larger than a thickness of the touch panel;

wherein a touch-panel flexible wiring substrate is connected to a specific side of the touch panel at the upper surface of the touch panel; and

wherein in the vicinity of the specific side of the touch panel, the adhesive sheet which extends over the display area of the touch panel at the upper surface of the touch panel between the touch panel and the front window is provided to surround without overlying a portion in which the touch-panel flexible wiring substrate is mounted to the upper surface of the touch panel,

wherein in the vicinity of the specific side of the touch panel, the adhesive sheet having a first side parallel to the specific side and a second side parallel to the specific side, the second side is nearer to the specific side by a distance d4, and a third side opposing to the first side and the second side,

wherein the adhesive sheet exists at both sides of the touch-panel flexible wiring substrate by distance d4,

wherein when a width of the adhesive sheet between the second side and the third side is b and a width of the adhesive sheet between the first side and the third side is c, b is greater than c, and d4=b−

c,

wherein an edge of the front window extends further outward than an edge of the liquid crystal cell in the direction perpendicular to the specific side of the touch panel, and

wherein the touch-panel flexible wiring substrate does not electrically connect with the front window.

2. The liquid crystal display device according to claim 1,

wherein a thickness of the adhesive sheet is larger than a thickness of the touch-panel flexible wiring substrate.

9. The liquid crystal display device according to claim 1, wherein the display area is an image display area.

3. A liquid crystal display device comprising:

a liquid crystal display panel and backlight housed in a resin mold, wherein the liquid crystal display panel having an upper polarization plate on a liquid crystal cell and the liquid crystal display panel having a display area;

a touch panel attached to the upper polarization plate by an UV curable resin, wherein the touch panel has a display area, and the UV curable resin extends over an entirety of the display area of the liquid crystal display panel; and

a front window attached to the touch panel;

wherein an upper surface of the touch panel and the front window are bonded by an adhesive sheet disposed therebetween;

wherein the adhesive sheet extends over an entirety of the display area of the touch panel at the upper surface of the touch panel;

wherein the front window has a thickness which is larger than a thickness of the touch panel;

wherein a touch-panel flexible wiring substrate is connected to a specific side of the touch panel at the upper surface of the touch panel; and

wherein in the vicinity of the specific side of the touch panel, the adhesive sheet which extends over the display area of the touch panel at the upper surface of the touch panel between the touch panel and the front window has a first side parallel to the specific side, a first protrusion extending to the specific side, and a second protrusion extending to the specific side, the adhesive sheet being provided to surround without overlying a portion in which the touch-panel flexible wiring substrate is mounted to the upper surface of the touch panel, by the first side, the first protrusion, and the second protrusion at a predetermined distance,

wherein the first protrusion extends to the specific side of the touch panel by a distance d4, and the second protrusion extends to the specific side of the touch panel by a distance d4,

wherein the adhesive sheet exists at both sides of the touch-panel flexible wiring substrate by the distance d4,

wherein the adhesive sheet has a second side parallel to the specific side, the second side is nearer to the specific side by a distance d4, and a third side opposing to the first side and the second side,

wherein when a width of the adhesive sheet between the second side and the third side is b and a width of the adhesive sheet between the first side and the third side is c, b is greater than c and d4=b−

c,

wherein an edge of the front window extends further outward than an edge of the liquid crystal cell in the direction perpendicular to the specific side of the touch panel, and

wherein the touch-panel flexible wiring substrate does not electrically connect with the front window.

10. The liquid crystal display device according to claim 3, wherein the display area is an image display area.

4. A liquid crystal display device comprising:

a liquid crystal display panel backlight housed in a resin mold, wherein the liquid crystal display panel having an upper polarization plate on a liquid crystal cell, and the liquid crystal display panel having a display area;

a touch panel attached to the upper polarization plate by an UV curable resin, wherein the touch panel has a display area, and the UV curable resin extends over an entirety of the display area of the liquid crystal display panel; and

a front window attached to the touch panel;

wherein an upper surface of the touch panel and the front window are bonded by an adhesive sheet disposed therebetween;

wherein the adhesive sheet extends over an entirety of the display area of the touch panel at the upper surface of the touch panel;

wherein the front window has a thickness which is larger than a thickness of the touch-panel;

wherein a touch-panel flexible wiring substrate is connected to a specific side of the touch panel at the upper surface of the touch panel; and

wherein in the vicinity of the specific side of the touch panel, the adhesive sheet which extends over the display area of the touch panel at the upper surface of the touch panel between the touch panel and the front window has a first side parallel to the specific side,

a first protrusion extending to the specific side, and a second protrusion extending to the specific side, the adhesive sheet being provided to surround without overlying a portion in which the touch-panel flexible wiring substrate is mounted to the upper surface of the touch panel, by the first side, the first protrusion, and the second protrusion at a predetermined distance; and

wherein air bubbles aligned parallel to the specific side exist in the first or second protrusion of the adhesive sheet, and the air bubbles aligned parallel to the specific side do not exist in the vicinity of the first side,

wherein the first protrusion extends to the specific side of the touch panel by a distance d4, and the second protrusion extends to the specific side of the touch panel by a distance d4,

wherein the adhesive sheet exists at both sides of the touch-panel flexible wiring substrate by a distance d4,

wherein the adhesive sheet has a second side parallel to the specific side, the second side is nearer to the specific side by a distance d4, and a third side opposing to the first side and the second side,

wherein when a width of the adhesive sheet between the second side and the third side is b and a width of the adhesive sheet between the first side and the third side is c, b is greater than c and d4=b−

c,

wherein an edge of the front window extends further outward than an edge of the liquid crystal cell in the direction perpendicular to the specific side of the touch panel, and

wherein the touch-panel flexible wiring substrate does not electrically connect with the front window.

5. The liquid crystal display device according to claim 4, wherein the air bubbles are linearly aligned parallel to the specific side.

6. The liquid crystal display device according to claim 4, wherein the air bubbles formed in the first or second protrusion of the adhesive sheet in parallel to the specific side do not exist in the display area.

7. The liquid crystal display device according to claim 4, wherein the air bubbles exist in an area between the adhesive sheet and the touch panel, and wherein the front window has a thickness which is larger than a thickness of the touch panel.

8. The liquid crystal display device according to claim 4, wherein the display area is an image display area.