Liquid crystal display panel and device thereof

• US 7,355,662 B2
• Filed: 01/18/2001
• Issued: 04/08/2008
• Est. Priority Date: 01/20/2000
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Kamiya, Hiroyuki, Tsujimura, Takatoshi
• Primary Examiner(s): Nguyen; Dung T.
• Application Number:
  US09/764,621
• Publication Number:
  US 20010028422A1
• Time in Patent Office: 2,637 Days
• Field of Search: 349/42, 349/43, 349 96- 98, 349/86, 349/87, 349/143, 349/141, 349/114
• US Class Current: 349/96
• CPC Class Codes: G02F 1/133528 Polarisers
• CPC Class Codes: G02F 1/133565 inside the LC elements, i.e. between the cell substrates
• CPC Class Codes: G02F 1/134363 for applying an electric field parallel to the substrate, i.e. in-plane switching [IPS]
• CPC Class Codes: G02F 1/136295 Materials; Compositions; Manufacture processes

Abstract

A liquid crystal display capable of improving the brightness without depending on the aperture ratio. By setting a lower polarization plate between an array substrate and a color filter substrate, the light reflected from a metal film formed on the array substrate can directly return to a light guide plate. Therefore, the light recycling efficiency is improved and the brightness of the liquid crystal display is improved.

Claims

1. A liquid crystal display panel, comprising:

an array substrate including a driving element for controlling a driving voltage and a display electrode to which a voltage is applied through the driving element are formed;

a first polarization layer for polarizing the light passing through the array substrate;

a liquid crystal layer including a liquid crystal material;

a color filter substrate on which a color filter comprising a color-material film is formed; and

a second polarization layer for polarizing the light passing through the color filter substrate,

wherein the array substrate, the first polarization layer, the liquid crystal layer, the color filter substrate, and the second polarization layer are successively superposed.

2. The liquid crystal display panel according to claim 1, wherein a common electrode is formed on the array substrate and an electric field is generated in a direction parallel with the array substrate by applying a voltage between the display electrode and the common electrode.

3. The liquid crystal display device according to claim 1, wherein the array substrate comprises:

an insulating substrate;

a thin film transistor formed on the insulating substrate;

a polymer layer covering the insulating substrate and comprising polarization elements dispersed therein; and

the display electrode formed on the polymer layer and penetrating the polymer layer, a part of the display electrode conductively connecting with the thin film transistor.

4. The liquid crystal display device according to claim 1,

wherein the array substrate comprises at least one of a common electrode, a display electrode, a gate electrode, a source electrode, and a drain electrode interposing the array substrate and the first polarization layer, and

wherein at least one of the display electrode, the gate electrode, the source electrode, and the drain electrode reflects light emitted from the backlight unit back to the backlight unit.

5. The liquid crystal display device according to claim 4,

wherein at least one of the display electrode, the gate electrode, the source electrode, and the drain electrode comprises a reflective metal film.

6. The liquid crystal display panel according to claim 1, further comprising:

a backlight unit for illuminating the liquid crystal display panel from the outside of the array substrate,

wherein the backlight unit, the away substrate, the first polarization layer, the liquid crystal layer, the color filter substrate, and the second polarization layer are successively superposed,

wherein the away substrate comprises;

an insulating substrate;

a thin film transistor formed on the insulating substrate;

a polymer layer covering the insulating substrate and comprising polarization elements dispersed therein;

a display electrode formed on the polymer layer and penetrating the polymer layer, a part of the display electrode conductively connecting with the thin film transistor; and

a common electrode formed on the array substrate,

wherein the common electrode and the display electrode interpose the backlight unit and the first polarization layer,

wherein the display electrode comprises a reflective metal film that reflects light emitted from the backlight unit back to the backlight unit, and

wherein the reflected light directly returns to the backlight unit without passing through the polarization layer so as to improve the light-recycling efficiency of the backlight unit, thereby improving a brightness of the liquid crystal display compared to a brightness of a liquid crystal display in which light reflected from the array substrate returns to the backlight unit after passing through a polarization layer.

7. A liquid crystal display device, comprising:

an array substrate provided with an insulating substrate, a thin film transistor formed on the insulating substrate, a polymer layer which covers the insulating substrate and in which polarization elements are dispersed, and a display electrode which is formed on the polymer layer and penetrates the polymer layer and a part of which conductively connects with the thin film transistor;

a color filter substrate disposed so as to face the array substrate by keeping a predetermined gap with the array substrate; and

a liquid crystal layer located at the gap between the array substrate and the color filter substrate; and

a backlight unit for applying light to a liquid crystal display panel from the outside of the array substrate.