Backlight assembly improving light efficiency and display device provided with the same

• US 20060072342A1
• Filed: 08/11/2005
• Published: 04/06/2006
• Est. Priority Date: 08/13/2004
• Status: Abandoned Application

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Park, Jong-Dae, Choi, Jin-Sung, Kim, Dong-Hoon
• Application Number:
  US11/202,618
• Publication Number:
  US 20060072342A1
• Time in Patent Office: Days
• US Class Current: 362/620
• CPC Class Codes: G02B 6/0036 2-D arrangement of prisms, protrusions, indentations or roughened surfaces
• CPC Class Codes: G02B 6/0053 Prismatic sheet or layer; Brightness enhancement element, sheet or layer

Abstract

The present invention provides a backlight assembly improving light efficiency and a display device provided with the same. The backlight assembly according to the present invention includes a light source for emitting light, a light guiding plate for guiding the light emitted from the light source, and a prism sheet disposed on the light guiding plate, wherein the prism sheet collects light emitted from the light source. A plurality of prisms are discontinuously formed on the prism sheet in one direction, and an upper surface portion of the cross section of the respective prisms, which is taken along a width direction of the respective prisms, forms an arc.

Claims

1. A backlight assembly comprising:

a light source emitting light;

a light guiding plate guiding the light emitted from the light source; and

a prism sheet disposed on the light guiding plate, the prism sheet collecting the light emitted from the light source,

wherein a plurality of prisms are discontinuously formed on the prism sheet in one direction, and an upper surface portion of a cross section of the respective prisms, when the cross section is taken along a width direction of the respective prisms, forms an arc.

2. The backlight assembly of claim 1, wherein among the plurality of prisms, a height of a first prism is different from a height of a second prism, which is adjacent to the first prism.

3. The backlight assembly of claim 2, wherein a ratio of heights of the first prism and the second prism is in the range of about 2.5 to about 4.0.

4. The backlight assembly of claim 2, wherein a difference between heights of the first prism and the second prism is in the range of about 10 micrometers to about 25 micrometers.

5. The backlight assembly of claim 2, wherein about 85% to about 95% of light being incident on the first prism and the second prism is emitted from the first prism and the remainder of the light is emitted from the second prism.

6. The backlight assembly of claim 1, wherein a height of a prism of the prism sheet is decreased gradually toward both ends of the prism.

7. The backlight assembly of claim 6, wherein a width of a prism of the prism sheet is decreased gradually toward both ends of the prism.

8. The backlight assembly of claim 1, wherein a vertical angle of a prism of the prism sheet is substantially a right angle, wherein the vertical angle is an angle between a cutting surface of the cross section and a horizontal surface of the prism sheet.

9. The backlight assembly of claim 1, further including another prism sheet disposed adjacent to the prism sheet, the another prism sheet including a plurality of prisms discontinuously formed on the another prism, wherein a direction of formation of the prisms in the prism sheet is at substantially right angle to a direction of formation of the prisms in the another prism sheet.

10. A display device comprising:

a panel unit displaying images, and

a backlight assembly supplying light to the panel unit,

wherein the backlight assembly comprises;

a light source emitting light;

a light guiding plate guiding the light emitted from the light source; and

a prism sheet disposed on the light guiding plate, the prism sheet collecting the light emitted from the light source,

wherein a plurality of prisms are discontinuously formed on the prism sheet in one direction, and an upper surface portion of a cross section of the respective prisms forms an arc, when the cross section is taken along a width direction of the respective prisms.

11. The display device of claim 10, wherein among the plurality of prisms, a height of a first prism is different from a height of a second prism, which is adjacent to the first prism.

12. The display device of claim 11, wherein a ratio of heights of the first prism and second prism is in the range of about 2.5 to about 4.0.

13. The display device of claim 11, wherein a difference between heights of the first prism and the second prism is in the range of about 10 micrometers to about 25 micrometers.

14. The display device of claim 11, wherein about 85% to about 95% of light being incident on the first prism and the second prism is emitted from the first prism and the remainder of the light is emitted from the second prism.

15. The display device of claim 10, wherein a height of a prism of the prism sheet is decreased gradually toward both ends of the prism.

16. The display device of claim 15, wherein a width of a prism of the prism sheet is decreased gradually toward both ends of the prism.

17. The display device of claim 10, wherein a vertical angle of the prism sheet is substantially a right angle, wherein the vertical angle is an angle between a cutting surface of the cross section and a horizontal surface of the prism sheet.

18. The display device of claim 10, wherein the panel unit is a liquid crystal display panel.