Optical plate, method of manufacturing optical plate, backlight assembly and liquid crystal display device
View Patent ↗An optical plate includes a main body plate, and a plurality of lens patterns formed on a first surface of the main body plate, wherein the lens patterns are elongated in a first direction and arranged in parallel with each other in a second direction crossing the first direction, wherein a cross section of the lens patterns form a part of an ellipse shape, the ratio of a semi-major axis to a semi-minor axis of the ellipse shape ranging from about 1.65 to about 1.75.
1. An optical plate, comprising:
a main body plate; and
a plurality of lens patterns formed on a first surface of the main body plate, wherein the lens patterns are elongated in a first direction and arranged in parallel with each other in a second direction crossing the first direction,
wherein a cross section of the lens patterns forms a part of an ellipse shape, the ratio of a semi-major axis to a semi-minor axis of the ellipse shape ranging from about 1.65 to about 1.75.
2. The optical plate according to claim 1 , wherein an isosceles triangle formed by connecting opposite end points of a base line in the cross section and a summit point of the cross section has a base angle ranging from about 38° to about 44°.
3. The optical plate according to claim 1 , wherein an isosceles triangle formed by connecting opposite end points of a base line in the cross section and a summit point of the cross section has a height of about 40% to about 45% of a length of the base line.
4. The optical plate according to claim 1 , wherein an embossing pattern is formed on a second surface of the main body plate opposite to the first surface.
5. The optical plate according to claim 1 , further comprising an ultraviolet ray blocking layer formed on a second surface of the main body plate opposite to the first surface and including an ultraviolet ray blocking agent.
6. The optical plate according to claim 1 , wherein the main body plate is substantially transparent.
7. A method of manufacturing an optical plate, the method comprising:
providing a first roll and a second roll arranged to face each other; and
forming an optical plate by applying a raw fluid including a polymer material between the first and second rolls white rotating the first and second rolls in opposite directions,
the second roll including a plurality of concave lens patterns formed along a circumference thereof and arranged in parallel with each other in a lengthwise direction of the second roll, and
a cross section of the concave lens patterns forming a part of an ellipse shape, the ratio of a semi-major axis to a semi-minor axis of the ellipse shape ranging from 1.65 to 1.75.
8. The method according to claim 7 , wherein a concave embossing pattern is formed on the first roll.
9. The method according to claim 7 , wherein a temperature of the raw fluid is the same or higher than a glass transition temperature of the polymer material while passing between the first and second rolls.
10. A backlight assembly, comprising:
a light source; and
an optical plate disposed in front of the light source,
the optical plate including:
a main body plate; and
a plurality of lens patterns formed on a first surface of the main body plate facing an opposite direction relative to the light source, wherein the lens patterns are elongated in a first direction and arranged in parallel with each other in a second direction crossing the first direction,
wherein opposite end points of a base line in a cross section of the lens patterns and a summit point of the cross section form an isosceles triangle,
a height of the isosceles triangle being 40% to 45% of a length of the base line.
11. The backlight assembly according to claim 10 , wherein the cross section of the lens patterns forms a part of an ellipse shape.
12. The backlight assembly according to claim 11 , wherein the ratio of a semi-major axis to a semi-minor axis of the ellipse shape ranges from about 1.65 to about 1.75.
13. The backlight assembly according to claim 12 , wherein an embossing pattern is formed on a second surface of the main body plate facing the light source.
14. The backlight assembly according to claim 12 , wherein the light source comprises a plurality of lamps which is arranged in parallel with each other in the second direction and elongated in the first direction respectively.
15. A liquid crystal display device, comprising:
a liquid crystal display panel;
a light source disposed behind the liquid crystal display panel; and
an optical plate disposed between the liquid crystal display panel and the light source,
the optical plate including:
a main body plate;
a plurality of lens patterns formed on a first surface of the main body plate facing the liquid crystal display panel, wherein the lens patterns are elongated in a first direction and arranged in parallel with each other in a second direction crossing the first direction, and
opposite end points of a base line of a cross section in the tens patterns and a summit point of the cross section form a triangle,
a base angle of the triangle ranging from about 38° to about 44°.
16. The liquid crystal display device according to claim 15 , wherein the cross section of the lens patterns forms a part of an ellipse shape.
17. The liquid crystal display device according to claim 16 , wherein the ratio of a semi-major axis to a semi-minor axis of the ellipse shape ranges from about 1.65 to about 1.75.
18. The liquid crystal display device according to claim 15 , wherein the light source comprises a plurality of lamps arranged in parallel with each other in the second direction and elongated in the first direction respectively.
19. The liquid crystal display device according to claim 18 , wherein an embossing pattern is formed on a second surface of the main body plate facing the light source.