Light guide member and backlight unit including light guide member

• US 20080025687A1
• Filed: 03/23/2007
• Published: 01/31/2008
• Est. Priority Date: 07/04/2006
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Mobile Display Company Limited (Samsung Electronics Co. Ltd.)
• Inventors: Kim, Jae Myung, Park, Kyung Il, Lee, Dong Ho, Cho, Won Ki
• Granted Patent: US 7,457,510 B2
• Time in Patent Office: Days
• US Class Current: 385/146
• CPC Class Codes: G02B 6/0036 2-D arrangement of prisms, protrusions, indentations or roughened surfaces
• CPC Class Codes: G02B 6/0038 Linear indentations or grooves, e.g. arc-shaped grooves or meandering grooves, extending over the full length or width of the light guide
• 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

Abstract

A light guide member for guiding light may include a first pattern on a first side of the light guide member, the first pattern may include a plurality of first features extending along a first direction, and a plurality of second features extending along a second direction, wherein the first direction crosses the second direction, the first feature has a first feature size, the second feature has a second feature size, and the first feature size may be less than the second feature size.

Claims

1. A light guide member for guiding light, the light guide member comprising:

a first pattern on a first side of the light guide member, the first pattern including;

a plurality of first features extending along a first direction; and

a plurality of second features extending along a second direction, wherein;

the first direction crosses the second direction,

the first feature has a first feature size, the second feature has a second feature size, and the first feature size is less than the second feature size.

2. The light guide member as claimed in claim 1, further comprising a second side including a plurality of third features extending along a third direction.

3. The light guide member as claimed in claim 2, wherein the third features include at least one of a plurality of third grooves and a plurality of third projections.

4. The light guide member as claimed in claim 1, wherein the first features include at least one of a plurality of first grooves having a first depth and a plurality of first projections having a first height, and the second features include at least one of a plurality of second grooves having a second depth and a plurality of second projections having a second height.

5. The light guide member as claimed in claim 4, wherein the first pattern includes a plurality of the first grooves and a plurality of the second grooves, and the first grooves and the second grooves have a substantially V-like cross-sectional shape, taken along a direction crossing the first direction or the second direction, respectively.

6. The light guide member as claimed in claim 4, wherein the first pattern includes a plurality of the first grooves and a plurality of the second grooves, and the first depth is about one-half to about one-quarter of the second depth.

7. The light guide member as claimed in claim 4, wherein the first pattern includes a plurality of the first projections and a plurality of the second projections, the first height is about one-half to about one-quarter of the second height.

8. The light guide member as claimed in claim 4, wherein the first pattern includes a plurality of the first grooves and a plurality of the second grooves, and a first angle formed by two inner sides of the second grooves is about 140°

to about 170°

.

9. The light guide member as claimed in claim 4, wherein the first pattern includes a plurality of the first projections and a plurality of the second projections, and a first angle formed by two inner sides of the second projections is about 140°

to about 170°

.

10. The light guide member as claimed in claim 4, wherein the first pattern includes a plurality of the first grooves and a plurality of the second grooves, and a second angle formed by an inner side of one of the second grooves and a plane substantially parallel to a plane along which the light guide member extends is about 1.3°

to about 2.3°

.

11. The light guide member as claimed in claim 4, wherein the first pattern includes a plurality of the first projections and a plurality of the second projections, and a second angle formed by an inner side of one of the second projections and a plane substantially parallel to a plane along which the light guide member extends is about 1.3°

to about 2.3°

.

12. The light guide member as claimed in claim 4, wherein the first pattern includes a plurality of the first grooves and a plurality of the second grooves, and the first grooves have a first pitch and the second grooves have a second pitch, the second pitch being larger than the first pitch.

13. The light guide member as claimed in claim 12, wherein the second pitch is about 0.003 mm to about 0.3 mm.

14. The light guide member as claimed in claim 4, wherein the first pattern includes a plurality of the first projections and a plurality of the second projections, and the first projections have a first pitch and the second projections have a second pitch, the second pitch being larger than the first pitch.

15. The light guide member as claimed in claim 14, wherein the second pitch is about 0.003 mm to about 0.3 mm.

16. The light guide member as claimed in claim 1, further comprising a second pattern on the first side of the light guide member, the second pattern including a plurality of dot-like patterns.

17. The light guide member as claimed in claim 16, wherein the first pattern is formed on a first area of the first side of the light guide member and the second pattern is formed on a second area of the first side of the light guide member, the first area being different from the second area.

18. The light guide member as claimed in claim 17, wherein the second area is about 2% to about 4% of an entire area of the first side.

19. The light guide member as claimed in claim 17, wherein a diameter of the dot-like patterns is about 40 μ

m to about 50 μ

m.

20. The light guide member as claimed in claim 17, wherein the dot-like patterns are engraved patterns formed on the second area of the first side.

21. The light guide member as claimed in claim 17, wherein the dot-like patterns are projections formed on the second area of the first side.

22. A backlight unit (BLU) employable by a display device including a display panel, the BLU comprising:

a light guide member for guiding light incident thereon, the light guide member including a first side with a first pattern formed thereon, the first pattern including;

a plurality of first features extending along a first direction; and

a plurality of second features extending along a second direction, wherein;

the first direction crosses the second direction,

the first feature has a first feature size, the second feature has a second feature size, and the first feature size is less than the second feature size.

23. The BLU as claimed in claim 22, further comprising a light source, wherein:

the light guide member includes a second side with a second pattern formed thereon, the second pattern including a plurality of dot-like patterns,

the first pattern is formed on a first area of the first side of the light guide member and the second pattern is formed on a second area of the first side of the light guide member,

the first area is different from the second area, and

the second area is closer to the light source than the first area.

24. The BLU as claimed in claim 22, further comprising a light source, wherein the first direction is parallel to a zero-degree radiation angle of light from the light source, and the second direction is substantially perpendicular to the first direction.