Polarizing plate and optical display apparatus comprising the same
A polarizing plate and an optical display apparatus including the same are provided. A polarizing plate includes: a polarizer; and a pattern layer on a surface of the polarizer and including a first resin layer and a second resin layer facing the first resin layer, the first resin layer including a patterned portion located at at least a portion thereof facing the second resin layer, the patterned portion includes at least two embossed optical patterns and a flat section formed between a pair of adjacent embossed optical patterns, each of the embossed optical patterns includes an upper surface defining a wave pattern, and the wave pattern has a value of about 20% to 60%, as calculated according to Formula 1 herein, and a pitch of greater than about 100 μm and less than about 400 μm.
1. A polarizing plate comprising:
a polarizer; and
a pattern layer on a surface of the polarizer and comprising a first resin layer and a second resin layer facing the first resin layer, the first resin layer comprising a patterned portion located at at least a portion thereof facing the second resin layer,
wherein the patterned portion comprises at least two embossed optical patterns each extending along a first direction and a flat section between a pair of adjacent embossed optical patterns of the embossed optical patterns along a second direction crossing the first direction,
each of the embossed optical patterns extending along the first direction has an upper surface defining a wave pattern, and
the wave pattern has a value of about 20% to 60%, as calculated according to the following Formula 1:
(| H 1− H 2|/ H 1)×100,
where H1 denotes a maximum height (unit: μm) of the embossed optical pattern, as measured within the wave pattern, and H2 denotes a minimum height (unit: μm) of the same embossed optical pattern, as measured within the wave pattern, and
the wave pattern has a pitch along the first direction of greater than about 100 μm and less than about 400 μm.
2. The polarizing plate according to claim 1 , wherein
the wave pattern comprises a curved surface defined by a continuous succession of a convex surface and a concave surface, and
an uppermost point of one convex surface of a first embossed optical pattern is located between uppermost points of a pair of respective adjacent convex surfaces of a second embossed optical pattern adjacent to the first embossed optical pattern.
3. An optical display apparatus comprising the polarizing plate according to claim 2 .
4. The polarizing plate according to claim 2 , wherein the convex surface has a maximum length equal to a maximum length of the concave surface.
5. An optical display apparatus comprising the polarizing plate according to claim 4 .
6. The polarizing plate according to claim 2 , wherein the convex surface has a maximum length different from a maximum length of the concave surface.
7. An optical display apparatus comprising the polarizing plate according to claim 6 .
8. The polarizing plate according to claim 1 , wherein
the wave pattern comprises a curved surface defined by a continuous succession of a convex surface and a concave surface,
the convex surface has a maximum width greater than a maximum width of the concave surface, and
a difference between the maximum width of the convex surface and the maximum width of the concave surface is greater than 0.1 μm and less than or equal to 1 μm.
9. An optical display apparatus comprising the polarizing plate according to claim 8 .
10. The polarizing plate according to claim 1 , wherein each of the embossed optical patterns satisfies the following Formula 2:
1 <P/W≤ 10,
where P denotes a pitch (unit: μm) of the patterned portion and W denotes a maximum width (unit: μm) of the embossed optical pattern, and
the embossed optical pattern has a base angle θ of greater than or equal to about 75° and less than about 90°.
11. An optical display apparatus comprising the polarizing plate according to claim 10 .
12. The polarizing plate according to claim 1 , wherein each of the embossed optical patterns has a trapezoidal, rectangular, or square cross-section.
13. An optical display apparatus comprising the polarizing plate according to claim 12 .
14. The polarizing plate according to claim 1 , wherein the second resin layer directly adjoins the embossed optical patterns and the flat section.
15. An optical display apparatus comprising the polarizing plate according to claim 14 .
16. The polarizing plate according to claim 1 , wherein the first resin layer has a different index of refraction than the second resin layer.
17. The polarizing plate according to claim 16 , wherein the first resin layer has a smaller index of refraction than the second resin layer.
18. The polarizing plate according to claim 1 , wherein a longitudinal direction of each of the embossed optical patterns is at an angle of about −5° to about +5° with respect to an absorption axis direction of the polarizer.
19. The polarizing plate according to claim 1 , further comprising a protective layer on a surface of the pattern layer.
20. An optical display apparatus comprising the polarizing plate according to claim 1 .