Granted Patent B2

US 7,999,887 · App. 12/877,658 · Granted Aug 16, 2011

Abstract

Claims (49)

1. A liquid crystal display device comprising:

a liquid crystal panel;

a backlight which radiates light to the liquid crystal panel;

a light emitting element which is mounted on the backlight;

a light guide plate on which light from the light emitting element is incident;

the light guide plate having an upper surface which is arranged to face the liquid crystal panel;

the light guide plate having a bottom surface which is arranged to face the upper surface;

the bottom surface of the light guide plate having grooves formed therein delimited by at least a first slant surface and a second slant surface which extend at a slant at different angles with respect to the bottom surface, the first slant surface being arranged closer to a light emitting element side of the light guide plate than the second slant surface; and

a reflection sheet which reflects the light radiated from the bottom surface;

wherein a light reflected by at least one of the first slant surface, the second slant surface, and the reflection sheet radiate from the upper surface;

wherein a peak of an intensity of the light radiated from the upper surface is inclined in a direction away from the light emitting element;

wherein the grooves are formed to produce a first light which is reflected on the grooves and a second light which is radiated from the grooves and is reflected on the reflection sheet;

wherein the angle of the first slant surface with respect to the bottom surface is greater than the angle of the second slant surface with respect to the bottom surface; and

wherein an asymmetric prism sheet is arranged on the light guide plate.

2. A liquid crystal display device according to claim 1 , wherein the light emitting element is an LED.

3. A liquid crystal display device according to claim 1 , wherein the backlight includes an optical film between the upper surface of the light guide plate and the liquid crystal panel.

4. A liquid crystal display device comprising:

a liquid crystal panel; and

a flat lighting device which radiates a light to the liquid crystal panel;

wherein the flat lighting device includes:

a plurality of light emitting elements;

a light guide plate which radiates light from the light emitting elements to the liquid crystal panel;

the light guide plate having an upper surface which is arranged to face the liquid crystal panel in an opposed manner;

the light guide plate having a bottom surface which is arranged to face the upper surface in an opposed manner; and

the bottom surface having at least a first inclination surface and a second inclination surface formed thereon, the first and second inclination surfaces extending at different inclination angles with respect to the bottom surface;

wherein a first light is reflected on the first and second inclination surfaces;

wherein a second light is radiated from the first and second inclination surfaces;

wherein the first inclination surface is arranged closer to a light emitting elements side of the light guide plate than the second inclination surface, and the first inclination surface has a first angle with respect to the bottom surface which is greater than a second angle of the second inclination surface with respect to the bottom surface;

wherein the first and second light radiate from the upper surface;

wherein a peak of an intensity of the light radiated from the upper surface is inclined in a direction away from the light emitting elements; and

wherein an asymmetric prism sheet is arranged between the upper surface of the light guide plate and the liquid crystal panel.

5. A liquid crystal display device according to claim 4 , wherein each of the light emitting elements is an LED.

6. A liquid crystal display device according to claim 4 , wherein the flat lighting device includes an optical film between the upper surface of the light guide plate and the liquid crystal panel.

7. A liquid crystal display device comprising:

a liquid crystal display panel;

a backlight which radiates a light to the liquid crystal display panel;

a light emitting element which is mounted on the backlight;

a light guide plate on which light from the light emitting element is incident;

the light guide plate having a bottom surface;

the light guide plate having an upper surface which faces the bottom surface in an opposed manner; and

a reflection surface which is formed on the bottom surface of the light guide plate;

wherein the reflection surface includes a first reflection surface having a first angle and a second reflection surface having a second angle with respect to the bottom surface;

wherein the first angle is greater than the second angle;

wherein the light reflected on the first and second reflection surfaces are radiated from the upper surface;

wherein a peak of an intensity of the light radiated from the upper surface is inclined in a direction away from the light emitting element;

wherein the first reflection surface is arranged closer to a light emitting element side of the light guide plate than the second reflection surface; and

wherein an asymmetric prism sheet is arranged between the upper surface of the light guide plate and the liquid crystal display panel.

8. A liquid crystal display device according to claim 7 , wherein the light emitting element is an LED.

9. A liquid crystal display device according to claim 7 , wherein the backlight includes an optical film between the upper surface of the light guide plate and the liquid crystal display panel.

Assignments (8)