Light guide plate, back light assembly having the same and display apparatus having the same

• US 7,753,579 B2
• Filed: 10/25/2005
• Issued: 07/13/2010
• Est. Priority Date: 10/25/2004
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Kim, Jae-Kwang
• Primary Examiner(s): O'Shea; Sandra L
• Assistant Examiner(s): APENTENG, JESSICA MCMILLAN
• Application Number:
  US11/257,746
• Publication Number:
  US 20060087867A1
• Time in Patent Office: 1,722 Days
• Field of Search: 362600-634, 362/561
• US Class Current: 362/620
• CPC Class Codes: G02B 6/0018 Redirecting means on the surface of the light guide
• CPC Class Codes: G02B 6/0051 Diffusing sheet or layer
• CPC Class Codes: G02B 6/0055 Reflecting element, sheet or layer
• CPC Class Codes: G02B 6/0065 Manufacturing aspects; Material aspects

Abstract

In a light guide plate and a display apparatus having the light guide plate, the light guide plate includes an incident face and a first exiting face. The incident face receives a light provided from an exterior. The first exiting face includes a first area and a second area. A first light-controlling pattern is formed in the second area. The first exiting face guides the incident light to the first area by the first light-controlling pattern and exits the guided light.

Claims

1. A light guide plate comprising:

an incident face receiving an incident light provided from an exterior;

a first exiting face including;

a first area and a second area, the second area being adjacent to the incident face, and being disposed between the incident face and the first area, and

a first light-controlling pattern disposed in the second area to guide the incident light to the first area, the guided light by the first light-controlling pattern exiting from the first exiting face; and

a second exiting face including;

a third area and a fourth area, the fourth area being adjacent to the incident face, and overlapped with the second area of the first exiting face in a plan view, and

a second light-controlling pattern disposed in the fourth area and not disposed in the third area, the second light-controlling pattern guiding the incident light to the third area, the guided light exiting from the second exiting face.

2. The light guide plate of claim 1, wherein the second exiting face comprises a third light-controlling pattern disposed in the third area of the second exiting face.

3. The light guide plate of claim 1, wherein a distribution density of the first light-controlling pattern becomes greater as the distance from the incident face increases.

4. The light guide plate of claim 1, wherein a size of the first light-controlling pattern becomes smaller as the distance from the incident face increases.

5. The light guide plate of claim 1, wherein the first light-controlling pattern comprises a recess having a groove shape, and the recess is extended in a direction substantially in parallel with a surface of the incident face.

6. The light guide plate of claim 1, wherein the first light-controlling pattern has a substantially dot shape when viewed on a plane.

7. The light guide plate of claim 1, wherein the first light-controlling pattern comprises a plurality of protruded patterns having a different height with respect to a surface of the first exiting face.

8. The light guide plate of claim 1, wherein the first light-controlling pattern comprises a plurality of recessed patterns having a different depth with respect to the first exiting face.

9. The light guide plate of claim 1, wherein the first light-controlling pattern has a plurality of arched patterns arranged in succession when viewed on a plane.

10. The light guide plate of claim 1, wherein the second light-controlling pattern has a substantially zigzag shape when viewed on a plane.

11. The light guide plate of claim 1, wherein a distribution density of the second light-controlling pattern becomes greater as a distance from the incident face increases.

12. The light guide plate of claim 1, wherein a size of the second light-controlling pattern becomes smaller as a distance from the incident face increases.

13. The light guide plate of claim 1, wherein the second light-controlling pattern comprises a recess having a groove shape, and the recess is extended in a direction substantially in parallel with the incident face.

14. The light guide plate of claim 1, wherein the second light-controlling pattern has a substantially dot shape.

15. The light guide plate of claim 1, wherein the second light-controlling pattern comprises a plurality of protruded patterns having a different height with respect to the second exiting face.

16. The light guide plate of claim 1, wherein the second light-controlling pattern comprises a plurality of recessed patterns having a different depth with respect to the second exiting face.

17. The light guide plate of claim 1, wherein the second light-controlling pattern has a plurality of arches arranged in succession when viewed on a plane.

18. The light guide plate of claim 1, wherein the second light-controlling pattern has a substantially zigzag shape when viewed on a plane.

19. A back light assembly comprising:

a light source to generate a light; and

a light guide plate comprising;

an incident face receiving an incident light provided from an exterior;

a first exiting face including;

a first area and a second area, the second area being adjacent to the incident face, and being disposed between the incident face and the first area, and

a first light-controlling pattern disposed in the second area to guide the incident light to the first area, the guided light by the first light-controlling pattern exiting from the first exiting face; and

a second exiting face including;

a third area and a fourth area, the fourth area being adjacent to the incident face, and overlapped with the second area of the first exiting face in a plan view, and

a second light-controlling pattern disposed in the fourth area and not disposed in the third area, the second light-controlling pattern guiding the incident light to the third area, the guided light exiting from the second exiting face.

20. The back light assembly of claim 19, wherein the light source comprises a plurality of point light sources.

21. The back light assembly of claim 19, further comprising a first optical member to enhance brightness uniformity of a first light exiting from the first exiting face.

22. The back light assembly of claim 19, further comprising a second optical member to enhance uniformity of brightness of a second light exiting from the second exiting face.

23. The back light assembly of claim 19, further comprising a transflective member to reflect a portion of the second light from the second exiting face and transmit a remaining portion of the second light through the transflective member.

24. The back light assembly of claim 19, wherein the first light-controlling pattern has a plurality of arched patterns arranged in succession when viewed on a plane.

25. The back light assembly of claim 24, wherein a center portion of the arched patterns corresponds to a center portion of the light source.

26. The back light assembly of claim 19, wherein the first light-controlling pattern has a substantially zigzag shape when viewed on a plane.

27. The back light assembly of claim 26, wherein each of vertexes of the zigzag shape corresponds to a center portion of the light source.

28. A display apparatus comprising:

a first display panel including a first display area to display an image and a first light blocking area to block light; and

a back light assembly comprising a light source to generate a light and a light guide plate, the light guide plate including;

an incident face receiving an incident light provided from an exterior;

a first exiting face including;

a first area and a second area, the second area being adjacent to the incident face, and being disposed between the incident face and the first area, and

a first light-controlling pattern disposed in the second area to guide the incident light to the first area, the guided light by the first light-controlling pattern exiting from the first exiting face; and

a second exiting face including;

a third area and a fourth area, the fourth area being adjacent to the incident face, and overlapped with the second area of the first exiting face in a plan view, and

a second light-controlling pattern disposed in the fourth area and not disposed in the third area, the second light-controlling pattern guiding the incident light to the third area, the guided light exiting from the second exiting face.

29. The display apparatus of claim 28, further comprising a second display panel having a second display area to display the image and a second light blocking area to block the light.

30. The display apparatus of claim 28, further comprising a transflective member to reflect a portion of the second light from the second exiting face and transmit a remaining portion of the second light.

31. The display apparatus of claim 30, further comprising a reflecting member disposed between the transflective member and the second display panel, the reflecting member partially reflecting a light transmitted through the transflective member to the light guide plate, the reflecting member having an opening that has a substantially same size as the second display panel.