LIQUID CRYSTAL DISPLAY DEVICE ASSOCIATED WITH TOUCH PANEL

• US 20110304564A1
• Filed: 12/14/2010
• Published: 12/15/2011
• Est. Priority Date: 06/10/2010
• Status: Active Grant

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Display Co., Ltd.
• Inventors: KIM, Tae-Hwan, Hwang, Min-Woo
• Granted Patent: US 10,921,936 B2
• Time in Patent Office: Days
• US Class Current: 345/173
• CPC Class Codes: G06F 3/044 by capacitive means
• CPC Class Codes: G06F 3/0445 using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer
• CPC Class Codes: G09G 2300/0426 Layout of electrodes and connections
• CPC Class Codes: G09G 2330/06 Handling electromagnetic interferences [EMI], covering emitted as well as received electromagnetic radiation
• CPC Class Codes: G09G 3/3611 Control of matrices with row and column drivers

Abstract

To block noise and achieve slimness and integration, a liquid crystal display device includes according to an embodiment a liquid crystal panel including first and second substrates and a liquid crystal layer formed therebetween, a shielding electrode formed throughout the entire rear surface of the second substrate of the liquid crystal panel, a first polarizing plate formed on the shielding electrode, a third substrate formed above the first polarizing plate and including intersecting first and second electrodes, a touch FPC including a touch drive IC to control driving and sensing of the first and second electrodes, and a printed circuit board formed at one side of the liquid crystal panel and generating a main panel control signal to control driving of the liquid crystal panel, a touch control signal to control the touch drive IC, and a voltage signal.

Claims

1. A liquid crystal display device associated with a touch panel, comprising:

a liquid crystal panel including a first substrate and a second substrate positioned opposite to each other and a liquid crystal layer formed between the first and second substrates;

a shielding electrode formed throughout the entire rear surface of the second substrate of the liquid crystal panel;

a first polarizing plate formed on the shielding electrode;

a third substrate formed above the first polarizing plate and including intersecting first electrodes and second electrodes;

a touch FPC formed at one side of the third substrate and including a touch drive IC to control driving and sensing of the first and second electrodes; and

a printed circuit board formed at one side of the liquid crystal panel and generating a main panel control signal to control driving of the liquid crystal panel, a touch control signal to control the touch drive IC, and a voltage signal of a designated level.

2. The liquid crystal display device according to claim 1, wherein the printed circuit board is connected with the first substrate through a main panel FPC at one side of the first substrate.

3. The liquid crystal display device according to claim 2, wherein the touch control signal generated by the printed circuit board is applied to the touch drive IC through the touch FPC.

4. The liquid crystal display device according to claim 3, wherein the voltage signal of the designated level generated by the printed circuit board is applied to the shielding electrode.

5. The liquid crystal display device according to claim 4, wherein the voltage signal of the designated level generated by the printed circuit board is constant voltage or ground voltage.

6. The liquid crystal display device according to claim 5, wherein the shielding electrode is electrically connected with a ground pad electrode formed on the first substrate.

7. The liquid crystal display device according to claim 6, wherein the shielding electrode is electrically connected with the ground pad electrode through a conductive tape.

8. The liquid crystal display device according to claim 6, wherein the shielding electrode is electrically connected with the ground pad electrode through an Ag dot.

9. The liquid crystal display device according to claim 6, wherein the ground pad electrodes receives the voltage signal of the designated level through the printed circuit board and the main panel FPC.

10. The liquid crystal display device according to claim 9, wherein the touch control signal and the voltage signal of the designated level are simultaneously generated by the printed circuit board, and are respectively applied to the first and second electrodes and the shielding electrode.

11. The liquid crystal display device according to claim 1, wherein the shielding electrode and the first and second electrodes are transparent electrodes.

12. The liquid crystal display device according to claim 11, wherein the shielding electrode has a sheet resistance of less than 100Ω

/□

.

13. The liquid crystal display device according to claim 1, wherein the first electrodes and the second electrodes are formed on one surface which is not positioned opposite to the first polarizing plate.

14. The liquid crystal display device according to claim 1, wherein the first electrodes and the second electrodes are formed on another surface which is positioned opposite to the first polarizing plate.

15. The liquid crystal display device according to claim 1, wherein the third substrate is a glass substrate or a transparent insulating film.

16. The liquid crystal display device according to claim 15, wherein an adhesive layer is interposed between the third substrate and the first polarizing plate.

17. The liquid crystal display device according to claim 15, wherein an adhesive agent applied in a closed loop shape along the edge of the first polarizing plate is formed between the third substrate and the first polarizing plate.

18. The liquid crystal display device according to claim 1, further comprising a second polarizing plate on the lower surface of the first substrate.

19. The liquid crystal display device according to claim 1, wherein a thin film transistor array is provided in the first substrate, and a color filter array is provided in the second substrate.

20. The liquid crystal display device according to claim 1, further comprising a cover glass on the third substrate.