Liquid crystal display with built-in touch screen having particles for pressure concentration

• US 7,675,580 B2
• Filed: 05/07/2007
• Issued: 03/09/2010
• Est. Priority Date: 05/10/2006
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Rho, Soo Guy
• Primary Examiner(s): Schechter; Andrew
• Assistant Examiner(s): INADOMI, MICHAEL J
• Application Number:
  US11/745,284
• Publication Number:
  US 20070262967A1
• Time in Patent Office: 1,037 Days
• Field of Search: 345/174, 178/18.01, 178/18.03, 178/18.05, 349/12
• US Class Current: 349/12
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• CPC Class Codes: G02F 1/13394 spacers regularly patterned on the cell subtrate, e.g. walls, pillars G02F1/133377 takes precedence
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/047 using sets of wires, e.g. crossed wires

Abstract

The present invention relates to a liquid crystal display (LCD) panel with a built-in touch screen capable of maintaining touch sensitivity at a certain level regardless of touch circumstances, and an LCD having the LCD panel with a built-in touch screen. According to the present invention, there are provided an LCD panel with a built-in touch screen, comprising a first substrate; a second substrate positioned opposite to first substrate; a liquid crystal layer injected between first and second substrates; a sensing unit including a conductive column spacer and a conductive pad spaced apart from conductive column spacer by a predetermined interval to sense a touch point; and a plurality of pressure particles with certain hardness positioned on an outer surface of first substrate. Further, there is provided an LCD having the LCD panel with a built-in touch screen.

Claims

1. A liquid crystal display (LCD) panel with a built-in touch screen, comprising:

a first substrate;

a second substrate positioned opposite to the first substrate;

a liquid crystal layer between the first and second substrates;

a sensing unit positioned between said substrates including a conductive column spacer and a conductive pad spaced apart from the conductive column spacer by a predetermined interval to sense a touch point; and

a plurality of pressure particles having a predetermined hardness positioned on an outer surface of the first substrate,

wherein the plurality of pressure particles concentrate outer pressure on the first substrate to actuate the sensing unit with less deformation of the first substrate.

2. The LCD panel as claimed in claim 1, further comprising first and second polarizing plates attached respectively to outer surfaces of the first and second substrates.

3. The LCD panel as claimed in claim 1,

wherein the conductive column spacer is formed on the first substrate.

4. The LCD panel as claimed in claim 3, wherein the conductive column spacer is formed on the black matrix.

5. The LCD panel as claimed in claim 3, wherein the conductive column spacer comprises a projection including an insulative material and a conductive layer formed on the projection.

6. The LCD panel as claimed in claim 1, wherein the plurality of pressure particles are formed on an area of the first substrate to correspond to the conductive column spacer.

7. The LCD panel as claimed in claim 1, wherein the second substrate comprises:

a transparent insulative substrate;

a plurality of thin film transistors formed on the substrate; and

a plurality of pixel electrodes,

wherein the conductive pad is formed on the second substrate.

8. The LCD panel as claimed in claim 7, wherein the second substrate further comprises a first sensing line and a second sensing line electrically connected to the conductive pad.

9. The LCD panel as claimed in claim 7, wherein the conductive pad is made of the same material as the pixel electrode.

10. The LCD panel as claimed in claim 1, further comprising a spacer for maintaining a liquid crystal cell gap between the first and second substrates.

11. The LCD panel as claimed in claim 10, wherein the spacer includes a ball spacer or column spacer.

12. The LCD panel as claimed in claim 1, wherein the pressure particles are in the form of a ball.

13. The LCD panel as claimed in claim 1, wherein the size of the pressure particles is 1 to 100 μ

m.

14. The LCD panel as claimed in claim 1, wherein the pressure particles comprise a transparent material.

15. The LCD panel as claimed in claim 1, wherein the plurality of pressure particles are dropped at positions corresponding to the conductive column spacer and the conductive pad.

16. The LCD panel as claimed in claim 1, wherein the plurality of pressure particles are dispersed on the outer surface of first substrate at a predetermined dispersion density.

17. The LCD panel as claimed in claim 2, wherein the plurality of pressure particles are dispersed on an adhesive layer of the first polarizing plate at a predetermined dispersion density.

18. The LCD panel as claimed in claim 1, further comprising:

a controller for receiving a signal from the sensing unit to detect a voltage change and to create a coordinate of a touch point; and

a driver for receiving the coordinate from the controller to operate a pointer.

19. An LCD, comprising:

an LCD panel with a built-in touch screen including a first substrate, a second substrate positioned opposite to the first substrate, a liquid crystal layer interposed between the first and the second substrates, a sensing unit positioned between said substrates including a conductive column spacer and a conductive pad spaced apart from the conductive column spacer by a predetermined interval to sense a touch point, and a plurality of pressure particles with a certain hardness positioned on an outer surface of the first substrate; and

a backlight for providing light to the LCD panel,

wherein the plurality of pressure particles concentrate outer pressure on the first substrate to actuate the sensing unit with less deformation of the first substrate.

20. A liquid crystal display (LCD) panel with a built-in touch screen, comprising:

a first substrate, which is deformable under finger pressure;

a second substrate positioned opposite to the first substrate;

a liquid crystal layer between the first and second substrates;

a sensing unit positioned between said substrates for responding to the deformation of said first substrate; and

a plurality of pressure particles positioned on an outer surface of one of said substrates for concentrating said finger pressure to actuate said sensing unit with less deformation of said first substrate.