Controller, display device and method for controlling to reduce degradation of image quality with use

A display device comprising:

• a display panel;
• a data driver including a plurality of driver Integrated Circuits (ICs) configured to supply a data signal to the display panel, and to have a first characteristic and a second characteristic corresponding to variation between at least two driver ICs among the plurality of driver ICs;
• and
• a controller configured to:
• supply, to the data driver, a first voltage at a first time, the first voltage at a second time, a second voltage at a third time, and the second voltage at a fourth time,
• determine a first change value based on a difference between a first output signal of the data driver and a second output signal of the data driver, the first output signal being outputted by the data driver in response to the first voltage at the first time, the second output signal being outputted by the data driver in response to the first voltage at the second time,
• determine a second change value based on a difference between a third output signal of the data driver and a fourth output signal of the data driver, the third output signal being outputted by the data driver in response to the second voltage at the third time, the fourth output signal being received by the data driver in response to the second voltage at the fourth time, and
• change the first characteristic and the second characteristic based on the first change value and the second change value,
• operate in divided periods of a first detection period for detecting the first change value of the first characteristic and a second detection period for detecting the second change value of the first characteristic, which is performed after the first detection period expires,
• wherein a pixel-driving period and a characteristic change period operate separately, a driving current is generated in the pixel-driving period, and the controller operates the first detection period and the second detection period in the characteristic change period.

A controller comprising:

• a single voltage supply unit configured to sequentially supply a first voltage and a second voltage to a plurality of driver Integrated Circuits (ICs) when a pixel-driving period expires;
• and
• a characteristic change unit configured to:
• supply, to the data driver, a first voltage at a first time, the first voltage at a second time, a second voltage at a third time, and the second voltage at a fourth time,
• determine a first change value based on a difference between a first output signal of the data driver and a second output signal of the data driver, the first output signal being outputted by the data driver in response to the first voltage at the first time being received by the data driver, the second output signal being outputted by the data driver in response to the first voltage at the second time being received by the data driver,
• determine a second change value based on a difference between a third output signal of the data driver and a fourth output signal of the data driver, the third output signal being outputted by the data driver in response to the second voltage at the third time being received by the data driver, the fourth output signal being received by the data driver in response to the second voltage at the fourth time being received by the data driver, and
• change the first characteristic and the second characteristic based on the first change value and the second change value,
• wherein a pixel-driving period and a characteristic change period operate separately, and a driving current is generated in the pixel-driving period and the controller supply the first voltage and the second voltage to the data driver in the characteristic change period.

A control method for changing variations of a plurality of driver Integrated Circuits (ICs) that transmits a data signal to a display panel including a plurality of pixels, the control method comprising:

• transmitting a first voltage at a first time and the first voltage at a second time, to the plurality of driver ICs;
• calculating a first change value based on a difference between a first output signal of the data driver and a second output signal of the data driver, the first output signal being outputted by the data driver in response to the first voltage at the first time, the second output signal being outputted by the data driver in response to the first voltage at the second time;
• transmitting a second voltage at a third time, and the second voltage at a fourth time, to the plurality of driver ICs;
• detecting a second change value based on a difference between a third output signal of the data driver and a fourth output signal of the data driver, the third output signal being outputted by the data driver in response to the second voltage at the third time, the fourth output signal being received by the data driver in response to the second voltage at the fourth time;
• and
• changing and setting the first characteristic and the second characteristic using the first change value and the second change value,
• wherein a pixel-driving period and a characteristic change period operate separately, a driving current is generated in the pixel-driving period and the transmitting the first voltage and the second voltage in the characteristic change period.