IP Library Granted Patent US 7,190,425
Granted Patent B2
US 7,190,425 · App. 10/742,915 · Granted Mar 13, 2007

Liquid crystal display module

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Quick Facts
Patent No.
US 7,190,425
App. No.
10/742,915
Granted
Mar 13, 2007
Kind
B2
Abstract

A liquid crystal display module according to an embodiment of the present invention includes a lamp to generate light; a light guide panel to convert an incident light from the lamp into a surface light, having a first refractive index; a low refractive index layer fixed on the light guide panel, having a second refractive index, which is relatively lower than the first refractive index, so as to have the light incident to the light guide panel totally reflected on the border area with the light guide panel; and a reflective type of liquid crystal display panel to realize a picture by reflecting the light going out from the low refractive index layer.

Claims (35)

1. A liquid crystal display module, comprising:

a lamp generating light;

a light guide panel that converts an incident light from the lamp into a surface light, said light guide panel having a first refractive index;

a low refractive index layer on the light guide panel having a second refractive index which is lower than the first refractive index, reflecting the light incident to the light guide panel on the border area;

a reflective type of liquid crystal display panel that illuminates a picture by reflecting the light coming from the low refractive index layer; and

a condensing device located between the lamp and the light guide panel, said condensing device controls the angle distribution of the incident light to the light guide panel to reduce the difference between the first refractive index and the second refractive index.

2. The liquid crystal display module according to claim 1 , wherein the low refractive index layer is adhered to the light guide panel.

3. The liquid crystal display module according to claim 1 , wherein a condition in which light is totally reflected on the border surface of the light guide panel and the low refractive index layer is defined by 90°−sin −1 (1/the first refractive index)>sin −1 (the second refractive index/the first refractive index).

4. The liquid crystal display module according to claim 1 , wherein the first refractive index is 1.7 and the second refractive index is 1.35.

5. The liquid crystal display module according to claim 1 , further comprising:

a polarizing sheet on the low refractive index layer;

a phase difference compensation sheet on the polarizing sheet; and

a diffusion sheet on the phase difference compensation sheet.

6. The liquid crystal display module according to claim 5 , wherein the polarizing sheet is adhered to the low refractive index layer;

the phase difference compensation sheet is adhered to the polarizing sheet; and

the diffusion sheet is adhered to the phase difference compensation sheet.

7. The liquid crystal display module according to claim 5 , wherein the reflective type of liquid crystal display panel includes:

a lower substrate having a reflective electrode, the reflective electrode reflects the light going out from the low refractive layer; and

an upper substrate facing the lower substrate with liquid crystal therebetween.

8. The liquid crystal display module according to claim 5 , wherein the reflective type of liquid crystal display panel includes:

an upper substrate having a reflective electrode facing the light guide panel with liquid crystal therebetween, wherein the reflective electrode reflects the light going out from the low refractive layer.

9. The liquid crystal display module according to claim 1 , wherein a condition in which light is totally reflected on the border surface of the light guide panel and the low refractive index layer is defined by (90°−(condensed angle by condensing device)>sin −1 (the second refractive index/the first refractive index)).

10. The liquid crystal display module according to claim 1 , wherein the first refractive index is 1.5 and the second refractive index is 1.35.

11. The liquid crystal display module according to claim 1 , further comprising:

a polarizing sheet on the low refractive index layer;

a phase difference compensation sheet on the polarizing sheet; and

a diffusion sheet on the phase difference compensation sheet.

12. The liquid crystal display module according to claim 11 , wherein the polarizing sheet is adhered to the low refractive index layer;

the phase difference compensation sheet is adhered to the polarizing sheet; and

the diffusion sheet is adhered to the phase difference compensation sheet.

13. The liquid crystal display module according to claim 11 , wherein the reflective type of liquid crystal display panel includes:

a lower substrate having a reflective electrode, the reflective electrode reflecting the light going out from the low refractive layer; and

an upper substrate facing the lower substrate with liquid crystal therebetween.

14. The liquid crystal display module according to claim 11 , wherein the reflective type of liquid crystal display panel includes:

an upper substrate having a reflective electrode facing the light guide panel with liquid crystal therebetween, the reflective electrode reflecting the light going out from the low refractive layer.

Assignments (2)
CHANGE OF NAME Recorded Oct 17, 2008
From: LG. PHILIPS LCD CO., LTD.
To: LG DISPLAY CO., LTD.
Reel/Frame 021773/0029 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Dec 23, 2003
From: HONG, HYUNG KI
To: LG.PHILIPS LCD CO., LTD.
Reel/Frame 014843/0754 →