TOUCH SCREEN LIQUID CRYSTAL DISPLAY DEVICE AND SYSTEM DRIVING METHOD THEREFOR

• US 20060244736A1
• Filed: 07/28/2005
• Published: 11/02/2006
• Est. Priority Date: 04/28/2005
• Status: Abandoned Application

• Current Assignee: Novatek Microelectronics Corporation (Novatek Microelectronics Corp Limited)
• Original Assignee: Novatek Microelectronics Corporation (Novatek Microelectronics Corp Limited)
• Inventors: Tseng, Ching-Wu
• Application Number:
  US11/161,258
• Publication Number:
  US 20060244736A1
• Time in Patent Office: Days
• US Class Current: 345/173
• 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

A touch screen liquid crystal display (LCD) device is provided. In its design, a LCD panel and an input panel are integrated, to prevent damages or impurity contamination in the manufacturing and assembly process of the LCD, further to spare the additional analog-to digital converter and control circuit. With the driving method of the present invention, the touch screen LCD device with integrated display and input function doesn'"'"'t affect the original LCD display function. Moreover, the simple on/off driving mode also enhances the resolution requirement of the touch screen LCD.

Claims

1. A touch screen liquid crystal display (LCD) device, comprising:

a plurality of touch screen LCD units, each of the touch screen LCD units comprising;

a touch-point circuit activated by an input of a medium for producing a short-circuit current signal;

a pixel unit, for receiving and storing a gray-level voltage signal;

a touch screen horizontal line, for receiving a first voltage signal and transmitting the short-circuit current signal;

a scanning touch screen horizontal line, for transmitting a scanning voltage signal for turning on/off the pixel unit and transmitting the signal of the touch screen horizontal line; and

a gray-level touch screen vertical line, for receiving a second voltage signal and the gray-level voltage signal and transmitting the short-circuit current signal;

a driving region, comprising;

a bidirectional horizontal line driver, for outputting the scanning voltage signal and the first voltage signal and receiving the short-circuit current signal; and

a bidirectional vertical line driver, for outputting the gray-level voltage signal and the second voltage signal and receiving the short-circuit current signal; and

a plurality of switch units, each of the switch units comprising;

a high-voltage switch, for turning on/off the bidirectional horizontal line driver and the adjacent touch screen horizontal line; and

a control signal, for switching on/off the high-voltage switch.

2. The touch screen LCD device as recited in claim 1, wherein at an intersection of projections of the touch screen horizontal line and the gray-level touch screen vertical line, the touch-point circuit is formed, and when the touch-point circuit gets short-circuit, the first voltage signal and the second voltage signal provide a required voltage, at different time respectively, for the touch-point circuit to produce a short-circuit current.

3. The touch screen LCD device as recited in claim 1, wherein the touch-point circuit gets short-circuit or open-circuit due to an input of at least one medium including a light source, an electric field and a magnetic field, and a short-circuit current signal is generated when the touch-point circuit gets short-circuit.

4. The touch screen LCD device as recited in claim 1, wherein in the bidirectional horizontal line driver, a same circuit is in charge of both receiving and outputting signals.

5. The touch screen LCD device as recited in claim 1, wherein in the bidirectional horizontal line driver, two sets of circuits are in charge of receiving and outputting signals, respectively.

6. The touch screen LCD device as recited in claim 1, wherein in the bidirectional vertical line driver, a same circuit is in charge of both receiving and outputting signals.

7. The touch screen LCD device as recited in claim 1, wherein in the bidirectional vertical line driver, two sets of circuits are in charge of receiving and outputting signals, respectively.

8. The touch screen LCD device as recited in claim 1, wherein the high-voltage switch comprises at least one of a N-MOS (N-type metal oxide semiconductor) and a P-MOS (P-type metal oxide semiconductor).

9. The touch screen LCD device as recited in claim 1, wherein the high-voltage switch comprises a CMOS (complementary metal oxide semiconductor).

10. A system driving method, suitable for a touch screen LCD device, comprising:

inputting a change to trigger an electric variation of a touch-point circuit, and further to produce a short-circuit current signal;

determining a turn on/off status of a high-voltage switch by a control signal;

when the high-voltage switch is on, dividing the period into a first time segment and a second time segment;

when the control signal turns on the high-voltage switch, during the first time segment, a bidirectional horizontal line driver outputting a first voltage signal, further producing the short-circuit current signal when the touch-point circuit gets short-circuit, and transmitting the short-circuit current signal to a gray-level touch screen vertical line;

when the control signal still turns on the high-voltage switch, during the second time segment, the bidirectional vertical line driver outputting a second voltage signal, further producing the short-circuit current signal when the touch-point circuit gets short-circuit, and transmitting the short-circuit current signal to a touch screen horizontal line; and

when the control signal turns off the high-voltage switch, the bidirectional horizontal line driver outputting a scanning voltage signal, and the bidirectional vertical line driver outputting a gray-level voltage signal.

11. The system driving method as recited in claim 10, wherein the input change is caused by at least one medium including a light source, an electric field and a magnetic field.

12. The system driving method as recited in claim 10, wherein the control signal turns on a high-voltage switch with a positive high-voltage and turns off a high-voltage switch with a negative high-voltage.

13. The system driving method as recited in claim 10, wherein the control signal turns on a high-voltage switch with a negative high-voltage and turns off a high-voltage switch with a positive high-voltage.

14. The system driving method as recited in claim 10, wherein the control signal is a periodic signal.

15. The system driving method as recited in claim 10, wherein the control signal is a non-periodic signal.

16. The system driving method as recited in claim 10, wherein the high-voltage switch comprises at least one of an N-MOS and a P-MOS.

17. The system driving method as recited in claim 10, wherein the high-voltage switch comprises a CMOS.

18. The system driving method as recited in claim 10, wherein the first time segment is prior to the second time segment.

19. The system driving method as recited in claim 10, wherein the second time segment is prior to the first time segment.