Display device and method of testing sensing unit thereof

• US 7,365,562 B2
• Filed: 12/27/2006
• Issued: 04/29/2008
• Est. Priority Date: 02/20/2006
• Status: Expired due to Fees

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Jeon, Jin
• Primary Examiner(s): Tieu; Benny Q.
• Assistant Examiner(s): Kusumakar; Karen M
• Application Number:
  US11/616,389
• Publication Number:
  US 20070252614A1
• Time in Patent Office: 489 Days
• Field of Search: 324/770, 324/765, 324/769
• US Class Current: 324/760.01
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• CPC Class Codes: G02F 1/13452 Conductors connecting driver circuitry and terminals of panels
• CPC Class Codes: G02F 1/13454 Drivers integrated on the active matrix substrate G02F1/136277 takes precedence
• CPC Class Codes: G02F 1/13456 Cell terminals located on one side of the display only
• CPC Class Codes: G02F 1/136254 Checking; Testing
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/0447 Position sensing using the local deformation of sensor cells
• CPC Class Codes: G06F 3/047 using sets of wires, e.g. crossed wires
• CPC Class Codes: H01H 13/702 with contacts carried by or formed from layers in a multilayer structure, e.g. membrane switches
• CPC Class Codes: H01H 2219/01 Liquid crystal

Abstract

A display device includes first and second display signal lines, pixels, first and second sensing signal lines, first through fourth test lines for transmitting first through fourth test signals, a first switching element connected to the first and second test lines, and the first sensing signal line, second switching elements connected to the first switching element, the second test line, and a subset of first display signal lines, a third switching element connected to the third and fourth test lines, and the second sensing signal line, and fourth switching elements connected to the third switching element, the fourth test line, and a subset of second display signal lines.

Claims

1. A display device comprising:

a plurality of first display signal lines;

a plurality second display signal lines crossing the first display signal lines;

a plurality of pixels each respectively connected to one of the first display signal lines and one of the second display signal lines;

a plurality of first sensing signal lines, each respectively formed substantially parallel to a subset of the first display signal lines, each subset of first display signal lines forming a first display signal group;

a plurality of second sensing signal lines, each respectively formed substantially parallel to a subset of the second display signal lines, each subset of second display signal lines forming a second display signal group;

a plurality of first sensing units connected to the first sensing signal lines;

a plurality of second sensing units connected to the second sensing signal lines;

a plurality of first test circuits, each respectively connected to one of the first sensing signal lines and a corresponding one of the first display signal groups, the first test circuits supplied with first and second test signals, the first test circuits testing a state of the first sensing units by changing luminance of the pixels according to the state of the first sensing units; and

a plurality of second test circuits, each respectively connected to one of the second sensing signal lines and a corresponding one of the second display signal groups, the second test circuits supplied with third and fourth test signals, the second test circuits testing a state of the second sensing units by determining whether or not the pixels will operate according to the state of the second sensing units.

2. The display device of claim 1, wherein each first test circuit comprises:

a plurality of first switching elements respectively connected to one of the first display signal line groups, and of which an operation status changes in response to the first test signals; and

a second switching element connected to the plurality of first switching elements and one of the first sensing signal lines, the second switching element operating in response to the first test signals, and supplying a voltage of the second test signal to a pixel connected to the first display signal line group connected to the plurality of first switching elements.

3. The display device of claim 2, wherein each second test circuit comprises:

a plurality of third switching elements respectively connected to one of the second display signal line groups, and of which an operation status changes in response to the third test signal; and

a fourth switching element connected to the plurality of third switching elements and one of the second sensing signal lines, the fourth switching element operating in response to the third test signals, and supplying a voltage of the fourth test signal to a pixel connected to the second display signal line group connected to the plurality of third switching elements.

4. The display device of claim 3, wherein the first and third test signals are gate-on voltages.

5. The display device of claim 4, wherein the second test signal is a data voltage presenting a black gray.

6. The display device of claim 4, wherein the fourth test signal is a gate-on voltage.

7. The display device of claim 3, wherein the first and second test circuits are formed in an edge region of the display device.

8. The display device of claim 1, wherein the first and second sensing units are pressure sensors.

9. A display device comprising:

a plurality of first display signal lines;

a plurality of second display signal lines crossing the first display signal lines;

a plurality of pixels each respectively connected to one of the first display signal lines and one of the second display signal lines;

a plurality of first sensing signal lines, each respectively formed substantially parallel to a subset of the first display signal lines;

a plurality of second sensing signal lines, each respectively formed substantially parallel to a subset of the second display signal lines;

a first test line spaced apart from a pixel, and transmitting a first test signal;

a second test line spaced apart from the first test line, and transmitting a second test signal;

a first switching element connected to the first test line, the second test line, and one of the first sensing signal lines;

a plurality of second switching elements connected to one subset of the first display signal lines adjacent to the first switching element, the second test line, and the first sensing signal line connected to the first switching element;

a third test line spaced apart from the pixel, and transmitting a third test signal;

a fourth test line spaced apart from the third test line, and transmitting a fourth test signal;

a third switching element connected to the third test line, the fourth test line, and one of the second sensing signal lines; and

a plurality of fourth switching elements connected to one subset of the second display signal lines adjacent to the third switching element, the fourth test line, and the second sensing signal line connected to the third switching element.

10. The display device of claim 9, further comprising a sensing unit connected to each of the first and second sensing signal lines.

11. The display device of claim 10, wherein each sensing unit is a pressure sensor.

12. The display device of claim 10, wherein pixels, corresponding to a sensing unit in an abnormal state, present a gray corresponding to a magnitude of a voltage different from a magnitude of a voltage of the first test signal.

13. The display device of claim 9, wherein the first and second test lines are formed within a same layer of the display device as the second display signal lines and the third and fourth test lines are formed within a same layer of the display device as the first display signal lines.

14. A method of testing a sensing unit of a display device, the display device including:

a plurality of first display signal lines;

a plurality second display signal lines;

a plurality of pixels each respectively connected to one of the first display signal lines and one of the second display signal lines;

at least one first sensing signal line, each first sensing signal line respectively formed substantially parallel to a subset of the first display signal lines;

at least one second sensing signal line, each second sensing signal line respectively formed substantially parallel to a subset of the second display signal lines;

a first test line;

a second test line;

a first switching element of which an input terminal is connected to the first test line, a control terminal is connected to the second test line, and an output terminal is connected to one of the at least one first sensing signal lines;

a plurality of second switching elements of which input terminals are connected to the first switching element, control terminals are connected to the second test line, and output terminals are respectively connected to one subset of first display signal lines adjacent to the first sensing signal line connected to the first switching element;

a third test line;

a fourth test line;

a third switching element of which an input terminal is connected to the third test line, a control terminal is connected to the fourth test line, and an output terminal is connected to one of the at least one second sensing signal lines; and

,

a plurality of fourth switching elements of which input terminals are connected to the third switching element, control terminals are connected to the fourth test line, and output terminals are respectively connected to one subset of second display signal lines adjacent to the second sensing signal line connected to the third switching element,

the method comprising;

supplying a first test signal when first to second switching elements are turned on by supplying the first test signal having a first magnitude to the first test line and supplying a second test signal having a second magnitude to the second test line;

changing a state of the second test signal to a third magnitude that is less than the second magnitude;

supplying a fourth test signal to a corresponding pixel when the third to fourth switching elements are turned on by supplying a third test signal having a fourth magnitude to the third test line and supplying the fourth test signal having the second magnitude to the fourth test line; and

changing a state of the fourth test signal from the second magnitude to the third magnitude.

15. The method of claim 14, wherein the second magnitude is equal to a magnitude of a gate-on voltage.

16. The method of claim 15, wherein the third magnitude is equal to a magnitude of a gate-off voltage.

17. The method of claim 16, wherein the first magnitude is equal to a data voltage presenting a black gray.

18. The method of claim 16, wherein the fourth magnitude is equal to the magnitude of the gate-on voltage.

19. The method of claim 14, further comprising supplying the first test signal to the first display signal lines via the second switching elements, and supplying the third test signal to the second display signal lines via the fourth switching elements.

20. The method of claim 14, wherein the display further includes a sensing unit connected to each of the first and second sensing signal lines, and the method further includes determining whether a sensing unit is in an abnormal state by visually detecting whether any corresponding pixels present a gray corresponding to a magnitude of a voltage different from the first magnitude.