POLARIZER AND LIQUID CRYSTAL DISPLAY INCLUDING THE SAME

• US 20140139787A1
• Filed: 03/18/2013
• Published: 05/22/2014
• Est. Priority Date: 11/20/2012
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Inventors: NA, Gwan Young, DO, Hee Wook, KIM, Kwang-Hyun, KIM, Dae Won, KIM, Teck Soo, PARK, Seung Beom, SUH, Duck Jong, SHIN, Na Young, LEE, Sang-Gu, KIM, Ji-Hoon, KI, Boo-Kan
• Granted Patent: US 9,097,933 B2
• Time in Patent Office: Days
• US Class Current: 349/96
• CPC Class Codes: G02B 5/205 Neutral density filters
• CPC Class Codes: G02B 5/3041 comprising multiple thin layers, e.g. multilayer stacks
• CPC Class Codes: G02B 5/305 including organic materials, e.g. polymeric layers
• CPC Class Codes: G02F 1/133345 Insulating layers G02F1/1335, G02F1/1337, G02F1/135, G02F1/136 take precedence
• CPC Class Codes: G02F 1/133526 Lenses, e.g. microlenses or Fresnel lenses
• CPC Class Codes: G02F 1/133528 Polarisers
• CPC Class Codes: G02F 1/133536 Reflective polarizers G02F1/13362 takes precedence
• CPC Class Codes: G02F 1/133545 Dielectric stack polarisers
• CPC Class Codes: G02F 1/133634 the refractive index Nz perpendicular to the element surface being different from in-plane refractive indices Nx and Ny, e.g. biaxial or with normal optical axis

Abstract

A polarizer includes a reflective polarizer main body and an Rth compensation layer. The reflective polarizer main body includes a repetitively laminated structure, the repetitively laminated structure including two layers of different refractive indices repetitively disposed on one another. The Rth phase compensation layer is disposed at one side of the reflective polarizer main body. The Rth phase compensation layer is configured to compensate for a phase difference in an Rth direction.

Claims

1. A polarizer, comprising:

a reflective polarizer main body comprising a repetitively laminated structure, the repetitively laminated structure comprising two layers of different refractive indices repetitively disposed on one another; and

an Rth phase compensation layer disposed at one side of the reflective polarizer main body, the Rth phase compensation layer being configured to compensate for a phase difference in an Rth direction.

2. The polarizer of claim 1, further comprising:

a plurality of buffer layers,

wherein;

the reflective polarizer main body comprises three repetitively laminated structures,

at least one of the plurality of buffer layers is disposed between instances of the repetitively laminated structures, and

at least one of the plurality of buffer layers is disposed on a first outermost surface of the polarizer.

3. The polarizer of claim 1, wherein:

the Rth phase compensation layer comprises a triacetyl-cellulose (TAC) layer.

4. The polarizer of claim 1, wherein:

the Rth phase compensation layer comprises a negative C plate or a cyclo olefin polymer (COP).

5. The polarizer of claim 1, wherein:

the reflective polarizer main body comprises the Rth phase compensation layer; and

the Rth phase compensation layer is disposed on an outermost surface of the polarizer.

6. A polarizer, comprising:

at least one first repetitively laminated structure comprising two layers of different refractive indices repetitively disposed on one another; and

a second repetitively laminated structure comprising two layers of different refractive indices repetitively disposed on one another,

wherein one of the at least one first repetitively laminated structures is configured as a light incident surface of the polarizer and the second repetitively laminated structure is configured as a light dispersion surface of the polarizer, and

wherein a thickness ratio or a component ratio of the two layers of the at least one first repetitively laminated structure differs from a thickness ratio or a component ratio of the two layers of the second repetitively laminated structure.

7. The polarizer of claim 6, wherein:

the different thickness ratios or component ratios of the at least one first repetitively laminated structure and the second repetitively laminated structure are determined based on;

materials configuring a first refractive index layer and a second refractive index layer of each of the at least one first repetitively laminated structure and the second repetitively laminated structure, or

a thickness ratio or component ratio between the first refractive index layer and the second refractive index layer.

8. The polarizer of claim 6, wherein:

a thickness ratio between the first refractive index layer and the second refractive index layer in association with the second repetitively laminated structure is larger than a thickness ratio between the first refractive index layer and the second refractive index layer in association with the at least one first repetitively laminated structure.

9. The polarizer of claim 8, wherein:

the thickness ratio between the first refractive index layer and the second refractive index layer in association with the second repetitively laminated structure is greater than 0.644 and less than 10.

10. The polarizer of claim 6, further comprising:

a plurality of buffer layers,

wherein;

the polarizer comprises two first repetitively laminated structures and one second repetitively laminated structure,

a first one of the two first repetitively laminated structures is disposed on a first one of the plurality of buffer layers,

a second one of the plurality of buffer layers is disposed between at least one of the two first repetitively laminated structures and the second repetitively laminated structure, and

a third one of the plurality of buffer layers is disposed on the second repetitively laminated structure.

26. The polarizer of claim 8, wherein:

the thickness ratio between the at least one first refractive index layer and the second refractive index layer in association with the second repetitively laminated structure is greater than 1 and less than 10.

27. The polarizer of claim 10, wherein:

a fourth one of the plurality of buffer layers is disposed between the two first repetitively laminated structures.

11. A liquid crystal display, comprising:

an upper panel comprising;

an upper polarizer configured as an absorptive polarizer, and

an upper insulation substrate;

a lower panel comprising;

a lower polarizer, and

a lower insulation substrate;

a liquid crystal layer disposed between the upper panel and the lower panel; and

a backlight providing unit configured to supply light,

wherein the lower panel is disposed on the backlight providing unit, and

wherein the lower polarizer comprises;

a reflective polarizer main body comprising a repetitively laminated structure, the repetitively laminated structure comprising two layers of different refractive indices repetitively disposed on one another, and

an Rth phase compensation layer disposed at one side of the reflective polarizer main body, the Rth phase compensation layer being configured to compensate for a phase difference in an Rth direction.

12. The liquid crystal display of claim 11, wherein:

the lower polarizer further comprises a plurality of buffer layers;

the reflective polarizer main body comprises three repetitively laminated structures;

at least one of the plurality of buffer layers is disposed between instances of the repetitively laminated structures; and

at least one of the plurality of buffer layers is disposed on a first outermost surface of the lower polarizer.

13. The liquid crystal display of claim 11, wherein:

the Rth phase compensation layer comprises a triacetyl-cellulose (TAC) layer.

14. The liquid crystal display of claim 11, wherein:

the Rth phase compensation layer comprises a negative C plate or a cyclo olefin polymer (COP).

15. The liquid crystal display of claim 11, wherein:

the reflective polarizer main body comprises the Rth phase compensation layer; and

the Rth phase compensation layer is disposed on an outermost surface of the lower polarizer.

16. The liquid crystal display of claim 11, wherein:

the liquid crystal layer comprises liquid crystal molecules horizontally aligned when an electric field is not applied and vertically aligned when a vertical electric field is imposed on the liquid crystal layer.

17. A liquid crystal display, comprising:

an upper panel comprising;

an upper polarizer configured as an absorptive polarizer, and

an upper insulation substrate;

a lower panel comprising;

a lower polarizer, and

a lower insulation substrate;

a liquid crystal layer disposed between the upper panel and the lower panel; and

a backlight providing unit configured to supply light,

wherein the lower panel is disposed on the backlight providing unit,

wherein the lower polarizer comprises;

at least one first repetitively laminated structure comprising two layers of different refractive indices repetitively disposed on one other, and

a second repetitively laminated structure comprising two layers of different refractive indices repetitively disposed upon one another,

wherein the second repetitively laminated structure is disposed closer to the liquid crystal layer than the at least one first repetitively laminated structure, and

wherein a thickness ratio or a component ratio of the two layers of the at least one first repetitively laminated structure differs from a thickness ratio or a component ratio of the two layers of the second repetitively laminated structure.

18. The liquid crystal display of claim 17, wherein:

the different thickness ratios or component ratios of the at least one first repetitively laminated structure and the second repetitively laminated structure are determined based on;

materials configuring a first refractive index layer and a second refractive index layer of each of the at least one first repetitively laminated structure and the second repetitively laminated structure, or

a thickness ratio or component ratio between the first refractive index layer and the second refractive index layer.

19. The liquid crystal display of claim 17, wherein:

a thickness ratio between the first refractive index layer and the second refractive index layer in association with the second repetitively laminated structure is larger than a thickness ratio between the first refractive index layer and the second refractive index layer in association with the at least one first repetitively laminated structure.

20. The liquid crystal display of claim 19, wherein:

the thickness ratio between the first refractive index layer and the second refractive index layer in association with the second repetitively laminated structure is greater than 0.644 and less than 10.

21. The liquid crystal display of claim 17, wherein:

the lower polarizer further comprises a plurality of buffer layers;

the lower polarizer comprises two first repetitively laminated structures and one second repetitively laminated structure;

a first one of the two first repetitively laminated structures is disposed on a first one of the plurality of buffer layers;

a second one of the plurality of buffer layers is disposed between at least one of the two first repetitively laminated structures and the second repetitively laminated structure;

a third one of the plurality of buffer layers is disposed on the second repetitively laminated structure.

22. The liquid crystal display of claim 17, wherein:

the liquid crystal layer comprises liquid crystal molecules vertically aligned when an electric field is not applied and horizontally aligned when a vertical electric field is imposed on the liquid crystal layer;

or

the liquid crystal layer comprises liquid crystal molecules horizontally aligned when an electric field is not applied and rotate in a horizontal surface when a horizontal electric field is imposed on the liquid crystal layer.

28. The polarizer of claim 19, wherein:

the thickness ratio of the first refractive index layer to the second refractive index layer in association with the second repetitively laminated structure is greater than 1 and less than 10.

29. The polarizer of claim 21, wherein:

a fourth one of the plurality of buffer layers is disposed between the two first repetitively laminated structures.

23. A liquid crystal display, comprising:

an upper panel comprising;

an upper polarizer, and

an upper insulation substrate;

a lower panel comprising;

a lower polarizer, and

a lower insulation substrate;

a liquid crystal layer disposed between the upper panel and the lower panel; and

a backlight providing unit configured to supply light,

wherein the lower polarizer is disposed on the backlight providing unit,

wherein the lower polarizer comprises a repetitively laminated structure comprising two layers of different refractive indices repetitively disposed on one another, and

wherein the upper polarizer comprises a C plate, the upper polarizer being configured as an absorptive polarizer.

24. The liquid crystal display of claim 23, wherein:

the upper polarizer further comprises;

a polyvinyl alcohol (PVA) layer,

a triacetyl-cellulose (TAC) layer, and

a biaxial compensation layer; and

the TAC layer disposed on the PVA layer, the PVA layer is disposed on the C plate, and the C plate is disposed on the biaxial compensation layer.

25. The liquid crystal display of claim 23, wherein:

the liquid crystal layer comprises liquid crystal molecules vertically aligned when an electric field is not applied and horizontally aligned when a vertical electric field is imposed on the liquid crystal layer;

or

the liquid crystal layer comprises liquid crystal molecules horizontally aligned when the electric field is not applied and rotate in a horizontal surface when a horizontal electric field is imposed on the liquid crystal layer.