Transflective liquid crystal display device

• US 20010017679A1
• Filed: 12/06/2000
• Published: 08/30/2001
• Est. Priority Date: 12/06/1999
• Status: Active Grant

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Philips LCD Company Limited (LG Display Co., Ltd.)
• Inventors: Ha, Kyoung-Su, Baek, Heume-Il, Kim, Yong-Beom
• Granted Patent: US 6,493,051 B2
• Time in Patent Office: Days
• US Class Current: 349/113
• CPC Class Codes: G02F 1/133555 Transflectors
• CPC Class Codes: G02F 1/133626 providing two modes of illumination, e.g. day-night

Abstract

A transflective liquid crystal display device includes a liquid crystal panel, which can be used in the transparent mode and reflective mode, selectively. The transflective liquid crystal panel includes the pixel electrode having the transparent electrode and reflective electrode and the reflective film having the transmitting hole. Therefore, the light generated from the backlight device can pass through the transmitting hole and transparent electrode into the liquid crystal. Moreover, the light reflected in the reflective film can also pass through them into the liquid crystal without being absorbed by the lower polarizer. That is, the brightness of the transflective LCD device is improved.

Claims

1. A transflective liquid crystal display device, comprising:

an upper substrate;

a lower substrate;

a pixel electrode arranged on the lower substrate and having reflective and transmitting portions;

liquid crystal interposed between the upper substrate and the lower substrates;

a backlight device arranged under the lower substrate and irradiating the light to the liquid crystal through the transmitting portion of the pixel electrode; and

a reflector to prevent the light from the backlight device from radiating on the reflective portion of the pixel electrode.

2. The transflective LCD device of

claim 1

, further comprising, a lower retardation film under the lower substrate.

3. The transflective LCD device of

claim 2

, further comprising, a lower polarizer arranged under the lower retardation film.

4. The transflective LCD device of

claim 1

, wherein the reflector is positioned under the lower substrate.

5. The transflective LCD device of

claim 4

, wherein the reflector has a transmitting region in order to transmit the light from the backlight device to the transmitting portion of the pixel electrode.

6. The transflective LCD device of

claim 5

, wherein area of the transmitting region of the reflector is smaller than that of the transmitting portion of the pixel electrode.

7. The transflective LCD device of

claim 4

, further comprising, a lower polarizer under the lower substrate and wherein the reflector is arranged under the lower polarizer.

8. The transflective LCD device of

claim 7

, wherein the reflector has a transmitting region in order to transmit the light from the backlight device to the transmitting portion of the pixel electrode.

9. The transflective LCD device of

claim 8

, wherein area of the transmitting region of the reflector is smaller than that of the transmitting portion of the pixel electrode.

10. The transflective LCD device of

claim 1

, further comprising a polarizer on the lower substrate and wherein the reflector is positioned between the polarizer and the lower substrate.

11. The transflective LCD device of

claim 1

, wherein the reflective electrode is made of the metallic material selected from a group composing of Aluminum, Tungsten, Molybdenum and the like.

12. The transflective LCD device of

claim 1

, wherein the transparent portion is comprised of transparent conductive metallic material.

13. The transflective LCD device of

claim 1

, wherein the transparent portion of the pixel electrode is a transmitting hole.

15. The transflective LCD device of

claim 12

, wherein area of the transmitting region is smaller than that of the transmitting portion of the pixel electride.

14. The transflective liquid crystal display device, comprising:

an upper substrate;

an upper polarizer on the upper substrate;

color filters under the upper substrate;

a common electrode under the color filters;

liquid crystal under the common electrode;

a switching device under the liquid crystal;

a pixel electrode, under the liquid crystal, having the transmitting and reflective portions and having an electrical connection with the switching device;

a lower substrate under the pixel electrode;

a lower polarizer under the lower substrate;

a reflective film, under the lower polarizer, having transmitting region;

a backlight device, under the reflective film, irradiating the light; and

wherein the light from the backlight device reaches the transmitting portion of the pixel electrode through the transmitting area of the reflective film.

16. The transflective liquid crystal display device, comprising:

an upper substrate;

an upper retardation film on the upper substrate;

an upper polarizer on the upper retardation film;

color filters under the substrate;

a common electrode under the color filters;

liquid crystal under the common electrode;

a switching device under the liquid crystal;

a pixel electrode, under the liquid crystal, having the transmitting and reflective portions and having an electrical connection with the switching device;

a lower retardation film under the pixel electrode;

a lower polarizer under the lower retardation film;

a reflective film, under the lower polarizer, having transmitting region;

a substrate under the reflective film;

a backlight device, under the reflective film, irradiating the light; and

wherein the light from the backlight device reaches the transmitting portion of the pixel electrode through the transmitting area of the reflective film.