Liquid crystal display and method of fabricating the same

Patent metadata

Field	Value
Publication number	US-9454027-B2
Application number	US-201414508892-A
Country	US
Kind code	B2
Filing date	Oct 7, 2014
Priority date	May 27, 2014
Publication date	Sep 27, 2016
Grant date	Sep 27, 2016

Abstract

A liquid crystal display (LCD) comprises a light source configured to provide a first light having a first wavelength, a first wavelength conversion layer configured to convert the first light into a second light having a second wavelength longer than the first wavelength, and a first optical shutter which overlaps the first wavelength conversion layer, is configured to adjust transmittance of the first light or the second light, and comprises liquid crystal molecules and dichromatic dye.

First claim

What is claimed is:

1. A liquid crystal display (LCD) comprising:
a light source configured to provide a first light having a first wavelength;
a first wavelength conversion layer configured to convert the first light into a second light having a second wavelength longer than the first wavelength;
a first optical shutter which overlaps the first wavelength conversion layer, is configured to adjust transmittance of the first light or the second light, and comprises liquid crystal molecules and dichromatic dye;
a second wavelength conversion layer which is located on the same layer as the first wavelength conversion layer and is configured to convert the first light into a third light having a third wavelength longer than the first wavelength and different from the second wavelength;
a second optical shutter which overlaps the second wavelength conversion layer, is configured to adjust transmittance of the first light or the third light, and is formed of substantially the same material as the first optical shutter;
a transparent layer which is located on the same layer as the first wavelength conversion layer and the second wavelength conversion layer and is formed of a transparent material; and
a third optical shutter which overlaps the transparent layer, is configured to adjust the transmittance of the first light, and is formed of substantially the same material as the first optical shutter.

2. The LCD of claim 1 , wherein the first wavelength conversion layer comprises quantum dots or a phosphor.

3. The LCD of claim 1 , further comprising a pixel electrode which faces a common electrode with the first optical shutter interposed therebetween, wherein light transmittance of the first optical shutter varies according to a voltage difference between the pixel electrode and the common electrode.

4. The LCD of claim 1 , further comprising a selective light pass filter which is located on a path of the second light, is configured to reflect the first light, and is configured to transmit the second light.

5. The LCD of claim 1 , further comprising a selective light pass filter which is located on a path of the third light, is configured to reflect the first light, and is configured to transmit the third light.

6. The LCD of claim 1 , further comprising a long wavelength pass filter which is located on a path of the second light and a path of the third light, is configured to reflect the first light, and is configured to transmit the second light and the third light, wherein the long wavelength pass filter is not located in an area which overlaps the transparent layer.

7. The LCD of claim 1 , wherein the light source is configured to provide ultraviolet (UV) light or blue light.

8. A liquid crystal display (LCD) comprising:
a first pixel area which is defined in a substrate;
a first wavelength conversion layer which is located on the first pixel area and comprises quantum dots or a phosphor configured to convert, a color of light incident upon the first pixel area into a first color;
a first optical shutter which overlaps the first wavelength conversion layer and comprises liquid crystal molecules and dichromatic dye;
a second pixel area which is defined in the substrate and different from the first pixel area;
a second wavelength conversion layer which is located on the second pixel area and comprises quantum dots or a phosphor configured to convert a color of light incident upon the second pixel area into a second color different from the first color;
a second optical shutter which overlaps the second wavelength conversion layer and is formed of substantially the same material as the first optical shutter;
a third pixel area which is defined in the substrate and different from the first pixel area and the second pixel area;
a transparent layer which is located on the third pixel area and is formed of a transparent material; and
a third optical shutter which overlaps the transparent layer and is formed of substantially the same material as the first optical shutter.

9. The LCD of claim 8 , further comprising:
a pixel electrode which is located on a side of the first optical shutter;
wherein a common electrode which is located on an other side of the first optical shutter, is insulated from the pixel electrode, and defines a cavity between the pixel electrode and the common electrode,
wherein the first optical shutter is located within the cavity.

10. The LCD of claim 9 , further comprising a cover layer which covers the common electrode and seals the cavity.

11. The LCD of claim 8 , further comprising a selective light pass filter which is located between the substrate and the first wavelength conversion layer and between the substrate and the second wavelength conversion layer, is configured to reflect light of a third color, and is configured to transmit light of the first color and light of the second color, wherein the selective light pass filter is not located on the third pixel area.

12. A method of fabricating a liquid crystal display (LCD), the method comprising:
providing a first light having a first wavelength;
forming a first wavelength conversion layer, which comprises quantum dots or a phosphor, on a pixel area of a substrate, the first wavelength conversion layer converting the first light into a second light having a second wavelength longer than the first wavelength;
forming a first optical shutter which overlaps the first wavelength conversion layer, is configured to adjust transmittance of the first light or the second light, and comprises liquid crystal molecules and dichromatic dye;
forming a second wavelength conversion layer which is located on the same layer as the first wavelength conversion layer and is configured to convert the first light into a third light having a third wavelength longer than the first wavelength and different from the second wavelength;
forming a second optical shutter which overlaps the second wavelength conversion layer, is configured to adjust transmittance of the first light or the third light, and is formed of substantially the same material as the first optical shutter;
forming a transparent layer which is located on the same layer as the first wavelength conversion layer and the second wavelength conversion layer and is formed of a transparent material; and
forming a third optical shutter which overlaps the transparent layer, is configured to adjust the transmittance of the first light, and is formed of substantially the same material as the first optical shutter.

13. The method of claim 12 , further comprising, after the forming of the first wavelength conversion layer:
forming a pixel electrode on the first wavelength conversion layer;
forming a sacrificial layer on the pixel electrode;
forming a common electrode on the sacrificial layer;
forming a cover layer on the common electrode to cover the common electrode; and
forming a cavity between the pixel electrode and the common electrode by removing the sacrificial layer,
wherein the first optical shutter is located within the cavity.

14. The method of claim 12 , further comprising, before the forming of the first wavelength conversion layer, forming a selective light pass filter, which transmits the second light only, on the substrate.

Assignees

• Samsung Display Co Ltd

Inventors

• Lee Baek Hee
• Roh Nam Seok
• Park Hae Il
• Sim Mun Ki

Classifications

• G02F2203/02

  reflective · CPC title

• G02F1/13725

  based on guest-host interaction (G02F1/13762, G02F1/13737, take precedence) · CPC title

• G02F1/133514

  Colour filters · CPC title

• G02F1/133377 Primary

  Cells with plural compartments or having plurality of liquid crystal microcells partitioned by walls, e.g. one microcell per pixel · CPC title