Touch screen panel type liquid crystal display

• US 8,605,038 B2
• Filed: 11/12/2008
• Issued: 12/10/2013
• Est. Priority Date: 12/07/2007
• Status: Expired due to Fees

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Inventors: Cho, Jong-Whan
• Primary Examiner(s): Lao, Lun-Yi
• Assistant Examiner(s): Siddiqui, MD Saiful A
• Application Number:
  US12/269,347
• Publication Number:
  US 20090146945A1
• Time in Patent Office: 1,854 Days
• Field of Search: 345172-179, 345/156, 345/159, 345/102, 345/104, 349/12, 349/122, 349/162, 359/613, 178 1801- 1806, 463 37- 38
• US Class Current: 345/173
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes

Abstract

A liquid crystal display includes an upper substrate, a lower substrate, and a liquid crystal layer interposed between the upper substrate and the lower substrate. The upper substrate includes a first insulating substrate, a transparent conductive layer on the first insulating substrate, and a first polarizer on the transparent conductive layer. The lower substrate includes a second insulating substrate, a second polarizer on the second insulating substrate, and a thin film transistor layer. The second insulating substrate is between the thin film transistor layer and the second polarizer. The transparent conductive layer allows an electric field to be formed on the first polarizer, so that a position signal input unit, which contacts the first polarizer, is capacitively coupled with the transparent conductive layer.

Claims

1. A touch screen panel type liquid crystal display, comprising:

an upper substrate comprising a first insulating substrate, a transparent conductive layer on the first insulating substrate, and a first polarizer on the transparent conductive layer, the transparent conductive layer configured to receive a position detection current to form a capacitance with a position signal input unit, and the first polarizer configured to serve as a dielectric between the transparent conductive layer and the position signal input unit;

a lower substrate comprising a second insulating substrate, a second polarizer on the second insulating substrate, and a thin film transistor layer, the second insulating substrate being between the thin film transistor layer and the second polarizer;

a liquid crystal layer between the upper substrate and the lower substrate;

a signal detection unit configured to measure first and second voltages at first and second side portions, respectively, of the transparent conductive layer, to thereby detect a contact position of the position signal input unit on the first polarizer based on a change in electrical load at the contact position through a conversion circuit caused by an absorption of electrical charges by the position signal input unit; and

a linear pattern at one surface of the transparent conductive layer to uniformly distribute an electric field on the first polarizer,

wherein the linear pattern is configured to receive a voltage when a position detection signal is applied to the transparent conductive layer.

2. The touch screen panel type liquid crystal display of claim 1, wherein the linear pattern comprises one material selected from the group consisting of silver, gold, copper, aluminum, and an alloy comprising at least two of silver, gold, copper, and aluminum.

3. The touch screen panel type liquid crystal display of claim 1, wherein the upper substrate further comprises an antistatic electrode, the first insulating substrate being between the antistatic electrode and the transparent conductive layer.

4. The touch screen panel type liquid crystal display of claim 1, wherein the signal detection unit is configured to detect the contact position of the position signal input unit through a 4-edge detection scheme or a 4-corner detection scheme.

5. The touch screen panel type liquid crystal display of claim 1, wherein the transparent conductive layer comprises a transparent conductive material selected from the group consisting of indium tin oxide, indium zinc oxide, and a mixture of indium tin oxide and indium zinc oxide.

6. A touch screen panel type liquid crystal display, comprising:

an upper substrate comprising a first insulating substrate, a first polarizer on the first insulating substrate, and a transparent conductive layer, the first insulating substrate being between the transparent conductive layer and the first polarizer, the transparent conductive layer configured to receive a position detection current to form a capacitance with a position signal input unit, and the first polarizer configured to serve as a dielectric between the transparent conductive layer and the position signal input unit;

a lower substrate comprising a second insulating substrate, a second polarizer on the second insulating substrate, and a thin film transistor layer, the second insulating substrate being between the thin film transistor layer and the second polarizer;

a liquid crystal layer between the upper substrate and the lower substrate;

a signal detection unit configured to dctcct measure first and second voltages at first and second side portions, respectively, of the transparent conductive layer, to thereby detect a contact position of the position signal input unit on the first polarizer based on a change in electrical load at the contact position through a conversion circuit caused by an absorption of electrical charges by the position signal input unit; and

a linear pattern at one surface of the transparent conductive layer to uniformly distribute an electric field on the first polarizer,

wherein the linear pattern is configured to receive a voltage when a position detection signal is applied to the transparent conductive layer.

7. The touch screen panel type liquid crystal display of claim 6, wherein the linear pattern comprises one material selected from the group consisting of silver, gold, copper, aluminum, and an alloy including at least two of silver, gold, copper, and aluminum.

8. The touch screen panel type liquid crystal display of claim 6, wherein the first insulating substrate has a thickness in the range of 0.01 mm to 5 mm.

9. The touch screen panel type liquid crystal display of claim 6, wherein the first insulating substrate comprises at least one polymer material selected from the group consisting of polycarbonate, polyethyleneterephthalate, polymethylmethacrylate, and polyethersulfone.

10. The touch screen panel type liquid crystal display of claim 6, wherein the signal detection unit is configured to detect the contact position of the position signal input unit through a 4-edge detection scheme or a 4-corner detection scheme.

11. A touch screen panel type liquid crystal display, comprising:

a liquid crystal display panel;

a transparent polymer layer on the liquid crystal display panel;

a transparent conductive layer on the transparent polymer layer;

an overcoat layer on the transparent conductive layer, the overcoat layer comprising a transparent insulating material, the transparent conductive layer configured to receive a position detection current to form a capacitance with a position signal input unit, and the overcoat layer configured to serve as a dielectric between the transparent conductive layer and the position signal input unit;

a signal detection unit configured to measure first and second voltages at first and second side portions, respectively, of the transparent conductive layer, to thereby detect a contact position of the position signal input unit on the overcoat layer based on a change in electrical load at the contact position through a conversion circuit caused by an absorption of electrical charges by the position signal input unit; and

a linear pattern at one surface of the transparent conductive layer to uniformly distribute an electric field on the overcoat layer,

wherein the linear pattern is configured to receive a voltage when a position detection signal is applied to the transparent conductive layer.

12. The touch screen panel type liquid crystal display of claim 11, wherein the overcoat layer comprises SiO₂.

13. The touch screen panel type liquid crystal display of claim 11, further comprising a cushion layer opposite the transparent conductive layer to absorb impact, the transparent polymer layer being between the cushion layer and the transparent conductive layer.

14. The screen panel type liquid crystal display of claim 13, wherein the cushion layer comprises silicon, thermosetting resin, or photo-curable resin.

15. The touch screen panel type liquid crystal display of claim 11, wherein the linear pattern comprises one material selected from the group consisting of silver, gold, copper, and aluminum, or an alloy including at least two of silver, gold, copper, and aluminum.

16. The touch screen panel type liquid crystal display of claim 11, further comprising an antistatic electrode, the transparent polymer layer being between the antistatic electrode and the transparent conductive layer.

17. The touch screen panel type liquid crystal display of claim 11, wherein

the transparent polymer layer comprises at least one polymer material selected from the group consisting of polycarbonate, polyethyleneterephthalate, polymethylmethacrylate, and polyethersulfone.