DISPLAY DEVICE

• US 20080150845A1
• Filed: 10/19/2007
• Published: 06/26/2008
• Est. Priority Date: 10/20/2006
• Status: Abandoned Application

• Current Assignee: Panasonic Liquid Crystal Display Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Liquid Crystal Display Company Limited (Panasonic Holdings Corporation)
• Inventors: Kohno, Tohru, Akimoto, Hajime, Kasai, Naruhiko, Ishii, Masato, Miyamoto, Mitsuhide
• Application Number:
  US11/874,961
• Publication Number:
  US 20080150845A1
• Time in Patent Office: Days
• US Class Current: 345/77
• CPC Class Codes: G09G 2320/029 by monitoring one or more pixels in the display panel, e.g. by monitoring a fixed reference pixel
• CPC Class Codes: G09G 2320/043 Preventing or counteracting the effects of ageing
• CPC Class Codes: G09G 2320/045 Compensation of drifts in the characteristics of light emitting or modulating elements
• CPC Class Codes: G09G 3/3208 organic, e.g. using organic light-emitting diodes [OLED]
• CPC Class Codes: G09G 3/3216 using a passive matrix
• CPC Class Codes: G09G 3/3225 using an active matrix

Abstract

A state of a deterioration (resistance change) of a display element is detected by a detecting unit through a switch and a detecting switch connected to a current source. On the basis of a detection result of the detecting unit, a display control unit corrects display data which is supplied to the display element.

Claims

1. A display device comprising:

a plurality of display elements;

a pixel control unit for controlling light emission amounts of said display elements in accordance with display data;

a displaying power source connected to said pixel control unit;

a signal line for inputting the display data to said display elements and outputting states of said display elements;

a detecting switch for switching the input of the display data to said signal line and the output of the states of the display elements;

a detecting power source connected to said detecting switch; and

a detecting unit for detecting the states of the display elements from said detecting switch,

wherein the states of said display elements are inputted to said detecting unit through said signal line and said detecting switch.

2. A device according to claim 1, wherein said detecting power source is a current source and said displaying power source is a voltage source.

3. A device according to claim 1, wherein said detecting unit holds a state of a reference element provided separately from said display elements and compares the state of said reference element with the states of said display elements.

4. A device according to claim 1, wherein said detecting unit holds states of a plurality of reference elements provided separately from said display elements and compares states of said reference elements with the states of said plurality of display elements.

5. A device according to claim 1, wherein said detecting unit compares states of the adjacent display elements.

6. A device according to claim 1, wherein said detecting unit compares the state of the display element selected as a reference element from said plurality of display elements with the states of the other display elements.

7. A device according to claim 1, wherein said detecting unit compares a state of a reference element provided separately from said display elements with the states of said display elements.

8. A device according to claim 5, wherein two current sources are connected as said detecting power source to said detecting unit.

9. A device according to claim 5, wherein two parallel resistors connected serially to said detecting power source are connected to said detecting unit.

10. A device according to claim 1, wherein a resistor which operates by a voltage source as said detecting power source is connected to said detecting unit.

11. A device according to claim 1, wherein said detecting unit is constructed by a plurality of comparators connected to a resistance rudder.

12. A device according to claim 1, further comprising a display control unit for correcting the display data on the basis of a detection result of said detecting unit.

13. A device according to claim 3, wherein said detecting power source is provided in common to said reference element and all of the display elements as detection targets.

15. A device according to claim 6, wherein two current sources are connected as said detecting power source to said detecting unit.

16. A device according to claim 7, wherein two current sources are connected as said detecting power source to said detecting unit.

17. A device according to claim 6, wherein two parallel resistors connected serially to said detecting power source are connected to said detecting unit.

18. A device according to claim 7, wherein two parallel resistors connected serially to said detecting power source are connected to said detecting unit.

14. A display device comprising:

a plurality of display elements;

a display control unit for transmitting a signal according to display data to said display elements through a signal line;

a voltage source which is common to said plurality of display elements;

a current source which is common to said plurality of display elements;

a detecting unit for detecting voltages of said display elements through said signal line; and

a control unit for controlling in such a manner that, for a first period of time, said voltage source and said display elements are connected, an output of the signal according to said display data of said display control unit and said display elements are connected, and said current source and said display elements are disconnected, and for a second period of time, said voltage source and said display elements are disconnected, the output of the signal according to said display data of said display control unit and said display elements are disconnected, and said current source and said display elements are connected,

wherein said current source is common to said display elements and a reference element serving as a reference of the detection,

for said first period of time, said display control unit transmits the signal according to said display data to said display elements through said signal line;

for said first period of time, said display elements emit light in accordance with the signal according to said display data and a voltage from said voltage source, and

for said second period of time, said detecting unit inputs the voltages of said display elements through said signal line and inputs the voltages of said reference elements.