LIQUID CRYSTAL DISPLAY DEVICE

• US 20140168574A1
• Filed: 12/12/2013
• Published: 06/19/2014
• Est. Priority Date: 12/19/2012
• Status: Abandoned Application

• Current Assignee: Japan Display Incorporated
• Original Assignee: Japan Display Incorporated
• Inventors: MATSUBARA, Kosuke
• Application Number:
  US14/104,721
• Publication Number:
  US 20140168574A1
• Time in Patent Office: Days
• US Class Current: 349/62
• CPC Class Codes: G02B 6/0051 Diffusing sheet or layer
• CPC Class Codes: G02B 6/0053 Prismatic sheet or layer; Brightness enhancement element, sheet or layer
• CPC Class Codes: G02B 6/0088 of the light guide or other optical sheets in the package
• CPC Class Codes: G02F 1/133308 Support structures for LCD panels, e.g. frames or bezels
• CPC Class Codes: G02F 1/13332 Front frames

Abstract

A liquid crystal display device includes a liquid crystal display panel and a backlight disposed on a back surface of the liquid crystal display panel. A light guide plate, a lower diffusion sheet and a lower prism sheet, are accommodated in a mold. An upper prism sheet extends over an upper surface of the mold, and bonded to the liquid crystal display panel and the mold with an adhesive. An edge of the upper prism sheet as the uppermost layer is invisible even when the screen is viewed from an oblique direction so as to prevent generation of an emission line due to the edge of the optical sheet. A sufficient bonding area is ensured between the mold and the liquid crystal display panel, and separation of the liquid crystal display panel from the mold is prevented under influence of damage.

Claims

1. A liquid crystal display device comprising a liquid crystal display panel and a backlight,

wherein the backlight includes a light guide plate, a mold which accommodates the light guide plate, and a plurality of optical sheets disposed on the light guide plate;

the mold has an upper surface which faces the liquid crystal display panel;

among the optical sheets, at least the optical sheet that is the closest to the liquid crystal display panel has a part which faces the upper surface of the mold; and

the liquid crystal display panel is bonded to the mold via the part which faces the upper surface of the mold.

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

wherein the liquid crystal display panel and the optical sheet that is the closest to the liquid crystal display panel are bonded, and the upper surface of the mold and the optical sheet that is the closest to the upper surface are bonded with a double-sided adhesive tape, respectively;

and

a whole region of the double-sided adhesive tape is overlapped with the upper surface of the mold in a planar view.

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

wherein some of the optical sheets including the optical sheet that is the closest to the liquid crystal display panel have parts which face the upper surface of the mold;

and

the liquid crystal display panel is bonded to the mold via the parts of some of the optical sheets, which face the upper surface of the mold.

4. The liquid crystal display device according to claim 3,

wherein all the optical sheets have parts which face the upper surface of the mold;

and

the liquid crystal display panel is bonded to the mold via the parts of all the optical sheets, which face the upper surface of the mold.

5. The liquid crystal display device according to claim 1, wherein the liquid crystal display panel is bonded to the mold only via the part of the optical sheet that is the closest to the liquid crystal display panel, which faces the upper surface of the mold.

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

wherein the optical sheets include a first diffusion sheet, a first prism sheet, and a second prism sheet disposed closer to the liquid crystal display panel than the first prism sheet;

and

the second prism sheet is the closest to the liquid crystal display panel.

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

wherein the optical sheets include a first diffusion sheet, a first prism sheet, a second prism sheet positioned closer to the liquid crystal display panel than the first prism sheet, and a second diffusion sheet positioned closer to the liquid crystal display panel than the first diffusion sheet;

and

the second diffusion sheet is the closest to the liquid crystal display panel.

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

wherein, the backlight has a light source which faces a first side of the light guide plate;

and

the part which faces the upper surface of the mold is positioned close to a second side of the light guide plate, which is different from the first side.

9. A liquid crystal display device including a liquid crystal display panel with a first substrate and a second substrate opposite the first substrate, having a first polarizing plate bonded to the first substrate and a second polarizing plate bonded to the second substrate, and a backlight disposed close to the first substrate of the liquid crystal display panel,

wherein the backlight includes a light guide plate, a mold which accommodates the light guide plate, and a plurality of optical sheets disposed on the light guide plate;

among the optical sheets, at least the optical sheet that is the closest to the liquid crystal display panel includes a first region positioned farther to the outside than an end part of the light guide plate; and

the first polarizing plate is bonded to the mold via the first region.

10. The liquid crystal display device according to claim 9, wherein an edge of the first region is positioned farther to the outside than an end part of the first polarizing plate.

11. The liquid crystal display device according to claim 9,

wherein the first polarizing plate and the first, region of the optical sheet that is the closest to the liquid crystal display panel are bonded, and the mold and the first region of the optical sheet that is the closest to the mold among the optical sheets are bonded with a double-sided adhesive tape, respectively;

and

a whole region of the double-sided adhesive tape is overlapped with the first region in a planar view.

12. The liquid crystal display device according to claim 9,

wherein some of the optical sheets including the optical sheet that is the closest to the liquid crystal display panel have the first regions;

and

the first polarizing plate is bonded to the mold via the first regions of some of the optical sheets.

13. The liquid crystal display device according to claim 12,

wherein all the optical sheets have the first regions;

and

the first polarizing plate is bonded to the mold via the first regions of all the optical sheets.

14. The liquid crystal display device according to claim 9, wherein the first polarizing plate is bonded to the mold only via a part of the optical sheet that is the closest to the liquid crystal display panel, which faces the first region.

15. The liquid crystal display device according to claim 9,

wherein the optical sheets include a first diffusion sheet, a first prism sheet, and a second prism sheet positioned closer to the liquid crystal display panel than the first prism sheet;

and

the second prism sheet is the closest to the liquid crystal display panel.

16. The liquid crystal display device according to claim 9,

wherein the optical sheets include a first diffusion sheet, a first prism sheet, a second prism sheet positioned closer to the liquid crystal display panel than the first prism sheet, and a second diffusion sheet positioned closer to the liquid crystal display panel than the first diffusion sheet;

and

the second diffusion sheet is the closest to the liquid crystal display panel.

17. The liquid crystal display device according to claim 9,

wherein the backlight has a light source which faces a first side of the light guide plate;

and

the first region is positioned close to a second side of the light guide plate, which is different from the first side.