Mirror effect liquid crystal display device using reflection polarizer

• US 20100020272A1
• Filed: 09/07/2007
• Published: 01/28/2010
• Est. Priority Date: 09/08/2006
• Status: Active Grant

• Current Assignee: LG Chem Limited (LG Corporation)
• Original Assignee: LG Chem Limited (LG Corporation)
• Inventors: Kim, Tae-Su, Shin, Bu-Gon, Shin, Hyun-Woo, Kim, Jac-Jin
• Granted Patent: US 8,054,417 B2
• Time in Patent Office: Days
• US Class Current: 349/96
• CPC Class Codes: G02F 1/133536 Reflective polarizers G02F1/13362 takes precedence

Abstract

A LCD (Liquid Crystal Display) device includes a backlight unit, a lower polarizer positioned on the backlight unit, a liquid crystal layer positioned on the lower polarizer, and an upper reflection polarizer positioned on the liquid crystal layer. The upper reflection polarizer is configured such that a regularly arranged metallic lattice is formed on a support this LCD device may give a good mirror effect when power is intercepted, and also give a clear display with high brightness even at a bright place when power is supplied to operate the LCD device.

Claims

1. A LCD (Liquid Crystal Display) device, comprising:

a backlight unit;

a lower polarizer positioned on the backlight unit;

a liquid crystal layer positioned on the lower polarizer; and

an upper reflection polarizer positioned on the liquid crystal layer,

wherein the upper reflection polarizer is configured such that a regularly arranged metallic lattice is formed on a support.

2. The LCD device according to claim 1, wherein the metallic lattice has a pattern selected from the group consisting of:

being coated on the support and protruded thereon;

being buried in a groove formed in the support;

being partially buried in the support and partially protruded thereon; and

being partially buried in the support and partially protruded thereon such that buried portions and protruded portions are alternately arranged.

3. The LCD device according to claim 1,

wherein the support has a single structure selected from the group consisting of a transparent film, a retardation film, an absorption polarizer and a substrate of a liquid crystal panel, or a multi-layered structure having at least two in combination selected therefrom.

4. The LCD device according to claim 3,

wherein, in case the support is an absorptive upper polarizer, a transmission axis of the metallic lattice is identical to a transmission axis of the absorptive upper polarizer

5. The LCD device according to claim 1,

wherein the metallic lattice has a rectangular, trapezoidal, parallelogrammic, triangular or circular section.

6. The LCD device according to claim 5,

wherein the metallic lattice has a section whose width to height ratio is 1:

½

to 1;

5.

7. The LCD device according to claim 6,

wherein the metallic lattice has a section whose width to height ratio is 1:

1 to 1;

3

8. The LCD device according to claim 1,

wherein the metallic lattice has a section whose width is 20 to 70% of an arrangement period of the metallic lattice.

9. The LCD device according to claim 1,

wherein the metallic lattice has an arrangement period of 300 nm or less.

10. The LCD device according to claim 9,

wherein the metallic lattice has an arrangement period of 200 nm or less.

11. The LCD device according to claim 1,

wherein the reflection polarizer is positioned at an uppermost portion of the LCD device, and

wherein the metallic lattice is positioned at an outer side based on the support, and a protective film is formed on a front surface of the support.

12. The LCD device according to claim 11,

wherein the protective film is made of material selected from the group consisting of PMMA (polymethyl methacrylate), TAC (tri-acetyl cellulose), PVA (polyvinyl alcohol), PI (polyimide), PET (polyethylene terephthalate), PEN (polyethylene naphthalate), PES (polyether sulphones), PC (polycarbonate) and COP (cyclic olefin polymer).

13. The LCD device according to claim 1,

wherein the lower polarizer is a lower reflection polarizer configured such that a regularly arranged metallic lattice is formed on a support.

14. The LCD device according to claim 13, wherein the metallic lattice has a pattern selected from the group consisting of:

being coated on the support and protruded thereon;

being buried in a groove formed in the support;

being partially buried in the support and partially protruded thereon; and

being partially buried in the support and partially protruded thereon such that buried portions and protruded portions are alternately arranged.

15. The LCD device according to claim 13,

wherein the support has a single structure selected from the group consisting or a transparent film, a retardation film, an absorption polarizer and a substrate of a liquid crystal panel, or a multi-layered structure having at least two in combination selected therefrom.

16. The LCD device according to claim 14,

wherein the support is an absorptive lower polarizer, and a transmission axis of the metallic lattice is identical to a transmission axis of the absorptive lower polarizer.

17. The LCD device according to claim 13,

wherein a transmission axis of the upper reflection polarizer is perpendicular to a transmission axis of the lower reflection polarizer.