Monolithic diffuser plate, and backlight unit and liquid crystal display device using the same

Patent metadata

Field	Value
Publication number	US-10036919-B2
Application number	US-201715712565-A
Country	US
Kind code	B2
Filing date	Sep 22, 2017
Priority date	Oct 28, 2016
Publication date	Jul 31, 2018
Grant date	Jul 31, 2018

Abstract

A monolithic diffuser plate for a backlight unit or a liquid crystal display (LCD) device can include a base substrate made of transparent glass, a monolithic diffusion sheet part integrated on a front surface of the base substrate, and a hiding diffusion part integrated on a rear surface of the base substrate for increasing a hiding power of the base substrate. The monolithic diffuser plate can increase a hiding power for hiding individual light sources in a backlight unit, prevent deformations caused by temperature variations and surrounding environmental factors, and minimize the thickness of a product using the monolithic diffuser plate while also increasing the reliability the product.

First claim

What is claimed is:

1. A monolithic diffuser plate comprising:
a base substrate including transparent glass;
a monolithic diffusion sheet part integrated on a front surface of the base substrate; and
a hiding diffusion part integrated on a rear surface of the base substrate for increasing a hiding power of the base substrate.

2. The monolithic diffuser plate of claim 1 , wherein the hiding diffusion part includes screen-printed ink on the rear surface of the base substrate, and
wherein the screen-printed ink includes one or more of a base solvent, SiO 2 , TiO 2 , and a plurality of diffusion patterns having different sizes on the front or rear surface of the hiding diffusion part.

3. The monolithic diffuser plate of claim 2 , wherein each of the plurality of diffusion patterns has a width larger than a width of each light source among a plurality of light sources in a backlight unit overlapping with the hiding diffusion part.

4. The monolithic diffuser plate of claim 2 , wherein the plurality of diffusion patterns are arranged in a plurality of diffusion pattern groups in the hiding diffusion part, and
wherein diffusion patterns within each of the plurality of diffusion pattern groups decrease in size from a center toward an edge of the corresponding diffusion pattern group.

5. The monolithic diffuser plate of claim 1 , wherein the monolithic diffusion sheet part comprises:
an optical diffusion sheet directly bonded to the front surface of the base substrate, and configured to diffuse light from the base substrate;
a prism sheet disposed on the optical diffusion sheet and configured to condense light from the optical diffusion sheet into front light; and
a dispersed TRP (Toray Reflective Polarizer) sheet disposed on the prism sheet and configured to increase brightness of the front light emitted from the prism sheet.

6. The monolithic diffuser plate of claim 5 , wherein the dispersed TRP sheet includes polycarbonate layers and dispersed core layers which are alternately laminated.

7. The monolithic diffuser plate of claim 6 , wherein the dispersed core layers include a plurality of cores that are entangled with each other according to a preset pattern.

8. The monolithic diffuser plate of claim 7 , wherein the plurality of cores forming the dispersed core layer each have a structure in which a CoPEN-based external core surrounds a PEN-based internal core, and the CoPEN-based external core and the PEN-based internal core are entangled with each other to form a dispersed structure.

9. The monolithic diffuser plate of claim 1 , wherein the hiding diffusion part is formed through a roll-to-roll process and includes a plurality of air layers having a same size between a first diffusion member and a second diffusion member laminated to each other, and a bead layer is disposed on a rear surface of the first diffusion member or the second diffusion member, and
wherein the hiding diffusion part is integrated on the rear surface of the base substrate through a roll-to-glass process.

10. The monolithic diffuser plate of claim 1 , wherein the hiding diffusion part comprises:
a first diffusion member configured to diffuse light incident on a rear surface of the hiding diffusion part;
a bead layer disposed on a rear surface of the first diffusion member and including a plurality of beads;
an adhesive diffusion member disposed on a front surface of the first diffusion member and including a plurality of air layer formation grooves; and
a second diffusion member disposed on a front surface of the adhesive diffusion member and covering all of the plurality of air layer formation grooves, and having a front surface bonded to the rear surface of the base substrate,
wherein the first diffusion member, the bead layer, the adhesive diffusion member and the second diffusion member are laminated and integrated with each other.

11. A backlight unit comprising:
a reflecting plate disposed on an inner front surface of a bottom cover;
a plurality of light emitting modules disposed on a front surface of the reflecting plate and housed in the bottom cover; and
a monolithic diffuser plate disposed on front surfaces of the plurality of light emitting modules and housed in the bottom cover,
wherein the monolithic diffuser plate includes:
a base substrate including transparent glass,
a monolithic diffusion sheet part integrated on a front surface of the base substrate, and
a hiding diffusion part integrated on a rear surface of the base substrate for increasing a hiding power of the base substrate.

12. The backlight unit of claim 11 , wherein the hiding diffusion part includes screen-printed ink on the rear surface of the base substrate, and
wherein the screen-printed ink includes one or more of a base solvent, SiO 2 , TiO 2 , and a plurality of diffusion patterns having different sizes on the front or rear surface of the hiding diffusion part.

13. The backlight unit of claim 11 , wherein the monolithic diffusion sheet part comprises:
an optical diffusion sheet directly bonded to the front surface of the base substrate, and configured to diffuse light from the base substrate;
a prism sheet disposed on the optical diffusion sheet and configured to condense light from the optical diffusion sheet into front light; and
a dispersed TRP (Toray Reflective Polarizer) sheet disposed on the prism sheet and configured to increase brightness of the front light emitted from the prism sheet.

14. The backlight unit of claim 11 , wherein the hiding diffusion part is formed through a roll-to-roll process and includes a plurality of air layers having a same size between a first diffusion member and a second diffusion member laminated to each other, and a bead layer is disposed on a rear surface of the first diffusion member or the second diffusion member, and
wherein the hiding diffusion part is integrated on the rear surface of the base substrate through a roll-to-glass process.

15. The backlight unit of claim 11 , wherein the hiding diffusion part comprises:
a first diffusion member configured to diffuse light incident on a rear surface of the hiding diffusion part;
a bead layer disposed on a rear surface of the first diffusion member and including a plurality of beads;
an adhesive diffusion member disposed on a front surface of the first diffusion member and including a plurality of air layer formation grooves; and
a second diffusion member disposed on a front surface of the adhesive diffusion member and covering all of the plurality of air layer formation grooves, and having a front surface bonded to the rear surface of the base substrate,
wherein the first diffusion member, the bead layer, the adhesive diffusion member and the second diffusion member are laminated and integrated with each other.

16. A liquid crystal display (LCD) device comprising:
a liquid crystal panel defining a plurality of pixel regions for displaying an image; and
a backlight unit configured to irradiate light onto the liquid crystal panel,
wherein the backlight unit comprises:
a reflecting plate disposed on an inner front surface of a bottom cover,
a plurality of light emitting modules disposed on a front surface of the reflecting plate and housed in the bottom cover, and
a monolithic diffuser plate disposed on front surfaces of the plurality of light emitting modules and housed in the bottom cover, and
wherein the monolithic diffuser plate includes:
a base substrate including transparent glass,
a monolithic diffusion sheet part integrated on a front surface of the base substrate, and
a hiding diffusion part in

Assignees

• Lg Display Co Ltd

Inventors

• Park Kiduck
• Park Jongwan
• Chung Donghyun
• Park Junsoo

Classifications

• G02F1/133536

  Reflective polarizers (G02F1/13362 takes precedence) · CPC title

• G02F1/133504 Primary

  Diffusing, scattering, diffracting elements (associated to illuminating devices G02F1/133606) · CPC title

• G02F2001/133331

  Physics · mapped topic

• G02F1/133606 Primary

  including a specially adapted diffusing, scattering or light controlling members · CPC title

• G02F1/133553

  Reflecting elements (associated to illuminating devices G02F1/133605) · CPC title