Compensation film, and optical film and display device including the same

Patent metadata

Field	Value
Publication number	US-2016154159-A1
Application number	US-201514712662-A
Country	US
Kind code	A1
Filing date	May 14, 2015
Priority date	Dec 1, 2014
Publication date	Jun 2, 2016
Grant date	—

Abstract

A compensation film includes a first retardation layer comprising a polymer having negative birefringence, and a second retardation layer comprising a polymer having negative birefringence, where the first retardation layer has an in-plane retardation (R e1 ) in a range of about 180 nanometers to about 300 nanometers for incident light having a wavelength of about 550 nanometers, the second retardation layer has an in-plane retardation (R e2 ) in a range of about 60 nanometers to about 170 nanometers for the incident light having the wavelength of about 550 nanometers, and the entire in-plane retardation (R e0 ) of the first retardation layer and the second retardation layer for incident light having wavelengths of about 450 nanometers and about 550 nanometers satisfies the following inequation: R e0 (450 nm)<R e0 (550 nm).

First claim

What is claimed is:

1 . A compensation film comprising:
a first retardation layer comprising a polymer having negative birefringence, and a second retardation layer comprising a polymer having negative birefringence, wherein the first retardation layer has an in-plane retardation (R e1 ) in a range of about 180 nanometers to about 300 nanometers for incident light having a wavelength of about 550 nanometers, the second retardation layer has an in-plane retardation (R e2 ) in a range of about 60 nanometers to about 170 nanometers for the incident light having the wavelength of about 550 nanometers, and an entire in-plane retardation (R e0 ) of the first retardation layer and the second retardation layer for incident light having wavelengths of about 450 nanometers and about 550 nanometers satisfies the following inequation: R e0 (450 nm)<R e0 (550 nm).

2 . The compensation film according to claim 1 , wherein the entire in-plane retardation (R e0 ) of the first retardation layer and the second retardation layer for the incident light having the wavelengths of about 450 nanometers and about 550 nanometers satisfies the following inequation: 0.7≦R e0 (450 nm)/R e0 (550 nm)<1.0.

3 . The compensation film according to claim 1 , wherein an angle between a slow axis of the first retardation layer and a slow axis of the second retardation layer is from about 20° to about 85°.

4 . The compensation film according to claim 1 , wherein an angle between a slow axis of the first retardation layer and a slow axis of the second retardation layer is from about 25° to about 80°.

5 . The compensation film according to claim 1 , wherein an angle between a slow axis of the first retardation layer and a slow axis of the second retardation layer is from about 30° to about 70°.

6 . The compensation film according to claim 1 , wherein an angle between a fast axis of the first retardation layer and a fast axis of the second retardation layer is from about 20° to about 80°.

7 . The compensation film according to claim 1 , wherein an angle between a fast axis of the first retardation layer and a fast axis of the second retardation layer may be from about 25° to about 75°.

8 . The compensation film according to claim 1 , wherein
the first retardation layer comprises an elongated polymer film comprising the polymer of the first retardation layer, refractive indices of the first retardation layer satisfy the following Inequation: n x1 <n y1 ≦n z1 or n x1 <n z1 ≦n y1 , wherein n x1 denotes a refractive index in an elongation direction of the polymer film of the first retardation layer, n y1 denotes an in-plane refractive index in a direction perpendicular to a direction of the n x1 , and n z1 denotes an out-of-plane refractive index in a direction perpendicular to both directions of n x1 and n y1 , the second retardation layer comprises an elongated polymer film comprising the polymer of the second retardation layer, and refractive indices of the second retardation layer satisfy the following inequation: n x2 <n y2 ≦n z2 or n x2 <n z2 ≦n y2 , wherein n x2 denotes a refractive index in an elongation direction of the polymer film of the second retardation layer, n y2 denotes an in-plane refractive index in a direction perpendicular to a direction of the n x2 , and n z2 denotes an out-of-plane refractive index in a direction perpendicular to both directions of n x2 and n y2 .

9 . The compensation film according to claim 1 , wherein each of the polymer of the first retardation layer and the polymer of the second retardation layer independently comprises at least one of polystyrene, poly(styrene-co-maleic anhydride), polymaleimide, poly(meth)acrylic acid, polyacrylonitrile, polymethyl(meth)acrylate, cellulose ester, poly(styrene-co-acrylonitrile), poly(styrene-co-maleimide), poly(styrene-co-methacrylic acid), a derivative thereof, a copolymer thereof, and a mixture thereof.

10 . The compensation film according to claim 1 , wherein
the first retardation layer has an in-plane retardation (R e1 ) in a range of about 200 nanometers to about 280 nanometers for the incident light having the wavelength of about 550 nanometers, and the second retardation layer has an in-plane retardation (R e2 ) in a range of about 80 nanometers to about 150 nanometers for the incident light having the wavelength of about 550 nanometers,

11 . An optical film comprising:
a polarizer; and the compensation film according to claim 1 .

12 . A display device comprising:
a display panel; a compensation film disposed on the display panel; and a polarizer disposed on the compensation film, wherein the compensation film comprises:
a first retardation layer comprising a polymer having negative birefringence; and
a second retardation layer comprising a polymer having negative birefringence,
wherein the first retardation layer has an in-plane retardation (R e1 ) in a range of about 180 nanometers (nm) to about 300 nm for incident light having a wavelength of about 550 nm, the second retardation layer has an in-plane retardation (R e2 ) in a range of about 60 nm to about 170 nm for the incident light having the wavelength of about 550 nm, and an entire in-plane retardation (R e0 ) of the first retardation layer and the second retardation layer for the incident light having wavelengths of about 450 nm and about 550 nm satisfies the following inequality: R e0 (450 nm)<R e0 (550 nm).

13 . The display device according to claim 12 , wherein the entire in-plane retardation (R e0 ) of the first retardation layer and the second retardation layer for the incident light having the wavelengths of about 450 nm and about 550 nm satisfies the following inequation: 0.7≦R e0 (450 nm)/R e0 (550 nm)<1.0.

14 . The display device according to claim 12 , wherein an angle between a slow axis of the first retardation layer and a slow axis of the second retardation layer is from about 20° to about 85°.

15 . The display device according to claim 12 , wherein an angle between a slow axis of the first retardation layer and a slow axis of the second retardation layer is from about 25° to about 80°.

16 . The display device according to claim 12 , wherein an angle between a fast axis of the first retardation layer and a fast axis of the second retardation layer is from about 20° to about 80°.

17 . The display device according to claim 12 , wherein an angle between a fast axis of the first retardation layer and a fast axis of the second retardation layer is from about 25° to about 75°.

18 . The display device according to claim 12 , wherein
the first retardation layer comprises an elongated polymer film comprising the polymer of the first retardation layer, refractive indices of the first retardation layer satisfy the following inequation: n x1 <n y1 ≦n z1 or n x1 <n z1 ≦n y1 , wherein n x1 denotes a refractive index in an elongation direction of the polymer film of the first retardation layer, n y1 denotes an in-plane refractive index in a direction perpendicular to a direction of the n x1 , and n z1 denotes an out-of-plane refractive index in a direction perpendicular to both directions of n x1 and n y1 , the second retardation layer comprises an elongated polymer film comprising the polymer of the second retardation layer, and refractive indices of the second retardation layer satisfy the following inequation: n x2 <n y2 ≦n z2 or n x2 <n z2 ≦n y2 , wherein n x2 denotes a refractive index in an elongation direction of the polymer film of the second retardation layer, n y2 deno

Assignees

• Samsung Electronics Co Ltd
• Samsung Sdi Co Ltd

Inventors

• Kim Hyung Jun
• Lee Ji-Hoon
• Kong Hye Young
• Won Jong Hoon
• Jung Myung Sup

Classifications

• H10K59/8791

  Arrangements for improving contrast, e.g. preventing reflection of ambient light · CPC title

• H10K59/879

  comprising refractive means, e.g. lenses · CPC title

• H01L51/5275

  Electricity · mapped topic

• G02F1/13363

  Birefringent elements, e.g. for optical compensation · CPC title

• H01L51/5281

  Electricity · mapped topic