Display Panel and Display Device

• US 20090225067A1
• Filed: 05/31/2006
• Published: 09/10/2009
• Est. Priority Date: 09/28/2005
• Status: Abandoned Application

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Aoki, Toshiya, Yoda, Kazuhiko
• Application Number:
  US11/992,518
• Publication Number:
  US 20090225067A1
• Time in Patent Office: Days
• US Class Current: 345/211
• CPC Class Codes: G02F 1/136254 Checking; Testing
• CPC Class Codes: G02F 1/136263 Line defects
• CPC Class Codes: G09G 2310/0267 Details of drivers for scan electrodes, other than drivers for liquid crystal, plasma or OLED displays
• CPC Class Codes: G09G 3/006 Electronic inspection or testing of displays and display drivers, e.g. of LED or LCD displays testing individual LED's G01R31/2635; testing lamps G01R31/44; testing of optical features of LCD displays G02F1/1309
• CPC Class Codes: G09G 3/20 for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters

Abstract

In one embodiment of the present invention, a display panel is disclosed in which a plurality of scanning lines and a plurality of signal lines are formed in a matrix shape, and in which driving transistors controlled to be turned ON/OFF by scanning voltages to be applied to scanning lines and pixel circuits connected with the signal lines through the driving transistors are disposed at the individual intersections between the scanning lines and the signal lines. The display panel includes a plurality of detecting transistors having their individual gates connected with the individual scanning lines. The plural detecting transistors have their drains commonly connected, and a detection signal indicating the logical sum of the ON states of the detecting transistors are outputted from the commonly connected drains.

Claims

1. A display panel

having a plurality of scanning lines and a plurality of signal lines formed to form a matrix, and

having, respectively at intersections between the scanning lines and the signal lines,

drive switching elements turned on and off according to scanning voltages fed to the scanning lines and

pixel circuits connected via the drive switching elements to the signal lines,

wherein

the display panel has detection switching elements of which control electrodes are connected respectively to the scanning lines, and

first conducting electrodes of the detection switching elements are connected together so that, from the first conducting electrodes thus connected together, a detection signal representing a logical sum of any on-state among the detection switching elements is outputted.

2. The display panel according to claim 1, wherein

the detection switching elements each turn on when receiving at control electrodes thereof a first-level scanning voltage that turns the drive switching elements on, and

turn off when receiving at the control electrodes thereof a second-level scanning voltage that turns the drive switching elements off.

3. The display panel according to claim 2, wherein

the drive switching elements and the detection switching elements are transistors formed on a single substrate by a single process.

4. A display device comprising:

the display panel according to claim 2;

a scanning line driver feeding the first-level scanning voltage to one after another of the scanning lines; and

a first wiring condition detector detecting, based on the detection signal, wiring condition of the scanning lines one by one.

5. A display device comprising:

the display panel according to claim 3;

a scanning line driver feeding the first-level scanning voltage to one after another of the scanning lines; and

a first wiring condition detector detecting, based on the detection signal, wiring condition of the scanning lines one by one.

6. The display device according to claim 4, wherein

the scanning voltage from the scanning line driver is fed to the scanning lines via first protection switching elements provided one for each of the scanning lines, and

the first wiring condition detector identifies as an abnormal scanning line any scanning line across which transmission of the first-level scanning voltage to a corresponding one of the detection transistors is abnormal, and turns off a corresponding one of the first protection switching elements which is inserted in the thus identified abnormal scanning line.

7. The display device according to claim 5, wherein

the scanning voltage from the scanning line driver is fed to the scanning lines via first protection switching elements provided one for each of the scanning lines, and

the first wiring condition detector identifies as an abnormal scanning line any scanning line across which transmission of the first-level scanning voltage to a corresponding one of the detection transistors is abnormal, and turns off a corresponding one of the first protection switching elements which is inserted in the thus identified abnormal scanning line.

8. The display device according to claim 4, further comprising:

a signal line driver connected to first ends of the signal lines; and

a second wiring condition detector connected to second ends of the signal lines,

wherein

while the scanning line driver is feeding the second-level scanning voltage to all the scanning lines, the signal line driver feeds an inspection voltage having a predetermined level to the signal lines so that, based on how the inspection voltage is transmitted, the second wiring condition detector detects wiring condition of the signal lines.

11. The display device according to claim 5, further comprising:

a signal line driver connected to first ends of the signal lines; and

a second wiring condition detector connected to second ends of the signal lines,

wherein

while the scanning line driver is feeding the second-level scanning voltage to all the scanning lines, the signal line driver feeds an inspection voltage having a predetermined level to the signal lines so that, based on how the inspection voltage is transmitted, the second wiring condition detector detects wiring condition of the signal lines.

12. The display device according to claim 6, further comprising:

a signal line driver connected to first ends of the signal lines; and

a second wiring condition detector connected to second ends of the signal lines,

wherein

while the scanning line driver is feeding the second-level scanning voltage to all the scanning lines, the signal line driver feeds an inspection voltage having a predetermined level to the signal lines so that, based on how the inspection voltage is transmitted, the second wiring condition detector detects wiring condition of the signal lines.

13. The display device according to claim 7, further comprising:

a signal line driver connected to first ends of the signal lines; and

a second wiring condition detector connected to second ends of the signal lines,

wherein

while the scanning line driver is feeding the second-level scanning voltage to all the scanning lines, the signal line driver feeds an inspection voltage having a predetermined level to the signal lines so that, based on how the inspection voltage is transmitted, the second wiring condition detector detects wiring condition of the signal lines.

9. A display device having

a display panel

having a plurality of scanning lines and a plurality of signal lines formed to form a matrix, and

having, respectively at intersections between the scanning lines and the signal lines,

drive switching elements turned on and off according to scanning voltages fed to the scanning lines and

pixel circuits connected via the drive switching elements to the signal lines,

a signal line driver connected to first ends of the signal lines, and

a scanning line driver feeding one after another of the scanning lines with a first-level scanning voltage that turns the drive switching elements on,

wherein the display device further comprises:

a second wiring condition detector connected to second ends of the signal lines.

wherein

while the scanning line driver is feeding all the scanning lines with a second-level scanning voltage that turns the drive switching elements off, the signal line driver feeds an inspection voltage having a predetermined level to the signal lines so that, based on how the inspection voltage is transmitted, the second wiring condition detector detects wiring condition of the signal lines.

10. The display device according to claim 9, wherein

the signal line driver is connected to the signal lines via second protection switching elements provided one for each of the signal lines, and

the second wiring condition detector identifies as an abnormal signal line any signal line across which transmission of the inspection voltage to the second wiring condition detector is abnormal, and turns off a corresponding one of the second protection switching elements which is inserted in the thus identified abnormal signal line.