Backlight module for a liquid crystal display

• US 20050265046A1
• Filed: 10/12/2004
• Published: 12/01/2005
• Est. Priority Date: 05/25/2004
• Status: Abandoned Application

• Current Assignee: AU Optronics Corporation
• Original Assignee: AU Optronics Corporation
• Inventors: Liu, Yao-Chi
• Application Number:
  US10/961,097
• Publication Number:
  US 20050265046A1
• Time in Patent Office: Days
• US Class Current: 362/606
• CPC Class Codes: G02B 6/0036 2-D arrangement of prisms, protrusions, indentations or roughened surfaces
• CPC Class Codes: G02B 6/004 Scattering dots or dot-like elements, e.g. microbeads, scattering particles, nanoparticles
• CPC Class Codes: G02B 6/0046 Tapered light guide, e.g. wedge-shaped light guide
• 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 6/0061 to provide homogeneous light output intensity
• CPC Class Codes: G02F 1/133606 including a specially adapted diffusing, scattering or light controlling members

Abstract

A backlight module for an LCD includes a light guide plate having a light incident surface and a light output surface adapted to face a display panel. A light source is provided for emitting light beams to the display panel from the light incident surface via the light output surface. And, it also includes a set of substantially identical bead-structured sheets stacked together and placed on the light output surface of the light guide plate for uniformly enhancing the light beams emitted from the light source without using any additional brightness enhancement sheet.

Claims

1. A backlight module for a Liquid Crystal Display comprising:

a light guide plate having a light incident surface and a light output surface adapted to face a display panel;

a set of substantially identical bead-structured sheets stacked together and placed on said light output surface of said light guide plate; and

a light source for emitting light beams to the display panel, the light beams traveling from said light incident surface through said set of substantially identical bead-structured sheets and directly to the display panel.

2. The backlight module according to claim 1, wherein said light source is positioned at an edgewise manner with respect to said light guide plate.

3. The backlight module according to claim 1, wherein said light source is positioned opposite to the light output surface of said light guide plate.

4. The backlight module according to claim 1, wherein each of said set of substantially identical bead-structured sheets is formed from a base sheet, a surface layer laminated on an upper surface of said base sheet, and a sticking-inhibiting layer laminated on a rear surface of said base sheet.

5. The backlight module according to claim 4, wherein said base sheet is formed from a transparent material selected from a group consisting of polyethylene terephthalate, polyethylene naphthalate, acrylic resin, polycarbonate, polystyrene, polyolefin, cellulose acetate, weather-resistant vinyl chloride and Polyester.

6. The backlight module according to claim 4, wherein said surface layer includes a binder and a plurality of transparent beads of different dimensions scattered randomly within said binder.

7. The backlight module according to claim 4, wherein said sticking-inhibiting layer includes a binder and a plurality of transparent beads scattered in said binder.

8. The backlight module according to claim 1, wherein said set of substantially identical bead-structured sheets includes at least two substantially identical bead-structured sheets.