Optical films for reducing color shift and organic light-emitting display apparatuses employing the same

1. An optical film, comprising:

a high refractive index pattern layer including a first surface and a second surface facing each other,

wherein the first surface includes a pattern having a plurality of grooves,

the plurality of grooves each have a curved surface and a depth greater than a width thereof, and

the high refractive index pattern layer is formed of a material having a refractive index greater than 1; and

a low refractive index pattern layer formed of a material having a refractive index smaller than the refractive index of the material constituting the high refractive index pattern layer,

wherein the low refractive index pattern layer includes a filling material for filling the plurality of grooves,

wherein a tilt angle, θ, of each groove satisfies the following condition, 15°≦θ≦75°,

the tilt angle is an angle between a straight line and the first surface,

the straight line connects an apex of the respective groove to a start point of an adjacent groove on the first surface, and

light incident through the low refractive index pattern layer is emitted through the second surface of the high refractive pattern layer.

2. The optical film of claim 1 , wherein

the plurality of grooves are collectively repeated in a cycle, C, and

the condition, A/C<0.5, is satisfied where A is the width of the groove.

3. The optical film of claim 1 , wherein the filling material includes air or a resin material.

4. The optical film of claim 1 , wherein

the low refractive index pattern layer is shaped in the form of a film having a plurality of protrusion patterns, and

the plurality of protrusion patterns corresponds to the plurality of grooves.

5. The optical film of claim 4 , wherein the low refractive index pattern layer includes a transparent plastic material including a light diffuser or a light absorber.

6. The optical film of claim 1 , wherein the plurality of grooves each have an extended stripe shape.

7. The optical film of claim 1 , wherein the plurality of grooves each have a dot shape from a perspective view with respect to the high refractive index pattern layer.

8. The optical film of claim 1 , wherein the curved surface of the plurality of grooves is an aspherical surface.

9. The optical film of claim 1 , further comprising:

an anti-reflection layer on the high refractive index pattern layer; and

a first adhesive layer under the low refractive index pattern layer.

10. The optical film of claim 9 , wherein a first base layer is between the high refractive index pattern layer and the anti-reflection layer.

11. The optical film of claim 10 , further comprising:

a circular polarization layer between the high refractive index pattern layer and the anti-reflection layer, the circular polarization layer including a phase shift layer and a linear polarization layer.

12. The optical film of claim 11 , wherein the first adhesive layer, the low refractive index pattern layer, the high refractive index pattern layer, the phase shift layer, the linear polarization layer, the first base layer, and the anti-reflection layer are sequentially arranged.

13. The optical film of claim 9 , further comprising:

a phase shift layer, a linear polarization layer, and a first base layer,

wherein the first adhesive layer, the phase shift layer, the linear polarization layer, the first base layer, and the low refractive index pattern layer are sequentially arranged.

14. The optical film of claim 9 , further comprising:

a transmittance adjusting layer between the high refractive index pattern layer and the anti-reflection layer.

15. An organic light-emitting display apparatus, comprising:

an organic light-emitting display panel including a plurality of pixels emitting light of different wavelengths, and a plurality of organic light-emitting layers each having a microcavity structure configured to resonate and emit light of a corresponding wavelength; and

the optical film according to claim 1 on the organic light-emitting display panel.

16. The organic light-emitting display apparatus of claim 15 , wherein the plurality of grooves each have an extended stripe shape.

17. The organic light-emitting display apparatus of claim 16 , wherein an extending direction of the plurality of grooves corresponds to a vertical direction of the organic light-emitting display panel.

18. The organic light-emitting display apparatus of claim 17 , wherein

the plurality of pixels are two-dimensionally arranged along a vertical direction and a horizontal direction of the organic light-emitting display panel, and

the extending direction of the grooves and the vertical direction in which the plurality of pixels are arranged are non-parallel to each other.

19. The organic light-emitting display device of claim 15 , further comprising:

a first adhesive layer between the organic light-emitting display panel and the low refractive index pattern layer; and

an anti-reflection layer on the high refractive index pattern layer.

20. The organic light-emitting display device of claim 19 , further comprising:

a circular polarization layer including a phase shift layer and a linear polarization layer.