Liquid crystal display device

• US 7,327,413 B2
• Filed: 05/17/2004
• Issued: 02/05/2008
• Est. Priority Date: 03/17/2001
• Status: Expired due to Fees

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Nobuyuki, Yamamura, Hwang, In-Sun, Kim, Sang-Il
• Primary Examiner(s): Dudek; James A.
• Application Number:
  US10/846,993
• Publication Number:
  US 20050024565A1
• Time in Patent Office: 1,359 Days
• Field of Search: 349/58, 349/112, 349/95
• US Class Current: 349/58
• CPC Class Codes: G02F 1/133504 Diffusing, scattering, diffracting elements associated to illuminating devices G02F1/133606

Abstract

Disclosed are an apparatus for changing a pathway of light according to a visual field angle to relax a gray scale inversion and for use in a liquid crystal display device in a twisted nematic mode, and the liquid crystal display device having the same. The light pathway partially changing apparatus is disposed on a liquid crystal display panel changes the pathway of the light partially so that a part of the light is substantially transmitted in the same direction as the light proceeds while the rest of the light is transmitted through a changed pathway, in order to change a brightness of the light according to a visual field angle of a liquid crystal display panel to restrain a gray scale inversion of the images while the light passes through the liquid crystal display panel to make the images on the liquid crystal display panel. The rest of the light transmitted through the changed pathway causes to obtain the visual field angle of the liquid crystal display panel, while restrains the gray scale inversion of the images along with the part of the light passing through the liquid crystal display panel in the same direction as that of the light transmitted through a center of the liquid crystal display panel.

Claims

1. A liquid crystal display device, comprising:

a front case;

a liquid crystal display panel arranged adjacent to the front case, the liquid crystal display panel comprising;

a member to change a pathway of light;

a liquid crystal layer disposed under the member to change a pathway of light; and

a polarizer disposed between the member to change a pathway of light and the liquid crystal layer, the member to change a pathway of light comprising a plurality of projections protruding toward the polarizer;

a backlight assembly comprising a lamp to generate the light for the liquid crystal display panel and being disposed under the liquid crystal display panel;

an optical sheet disposed between the backlight assembly and the liquid crystal display panel; and

a rear case arranged opposite the front case,

wherein each of the projection comprises a horizontal surface, a first inclined surface extending from a first end of the horizontal surface and a second inclined surface extending from a second end of the horizontal surface, which is opposite to the first end.

2. A liquid crystal display device in claim 1, wherein each of the projections has a stripe-shape.

3. The liquid crystal display device of claim 2, wherein the projections are substantially parallel with each other.

4. The liquid crystal display device of claim 2, wherein an inner angle defined by an extended line from the horizontal surface and one of the first and the second inclined surfaces is about 10 degree to 80 degree.

5. The liquid crystal display device of claim 2, wherein a ratio of a height of the projection to a length from a point at which an extended line of the first inclined surface intersects an extended line of the second inclined surface to a bottom of the projection is about 0.05 to 0.7:

1.

6. The liquid crystal display device of claim 2, wherein the member to change a pathway of light further comprises transparent base film on which the projections are formed.

7. The liquid crystal display device of claim 6, wherein the projections and the transparent base film comprise a same transparent film.

8. The liquid crystal display device of claim 7, wherein a refractive index of the projections and the transparent base film is about more than 1.4.

9. The liquid crystal display device of claim 8, wherein the transparent base film comprises a photosensitive polymer type material.

10. The liquid crystal display device of claim 2, wherein the member to change a pathway of light further comprises a transparent protective film to cover the projections.

11. The liquid crystal display device of claim 10, wherein a refractive index of the transparent protective film is about less than 1.35.

12. The liquid crystal display device of claim 11, wherein the transparent protective film comprises a fluorine-containing polymer type material.

13. The liquid crystal display device of claim 12, wherein the transparent protective film has an adhesiveness.