Display device and control method thereof
View Patent ↗A display device with improved brightness and a method of controlling the display device are presented. The display device includes a driving transistor, a pixel electrode electrically connected to the driving transistor, a detecting transistor detecting a magnitude of an electric signal transferred from the driving transistor to the pixel electrode, and a controller. The controller regulates a data voltage applied to the pixel electrode based on a difference between the detected electric signal and a predetermined reference level. The display device achieves improved homogeneity of brightness by compensating for any deterioration of TFTs.
1. A display device comprising:
a driving transistor;
a driving voltage line applying a driving voltage to the driving transistor;
a switching transistor connected to a gate electrode of the driving transistor;
a data line applying a data voltage to the switching transistor;
a first gate line applying a gate on voltage to the switching transistor;
a pixel electrode electrically connected to the driving transistor;
a detecting transistor detecting a magnitude of an electric signal transferred from the driving transistor to the pixel electrode; and
a controller regulating a voltage applied to the pixel electrode based on a difference between the detected electric signal and a predetermined reference level;
wherein a gate electrode of the detecting transistor is connected to a second gate line that is different from the first gate line.
2. The display device according to claim 1 , further comprising a detecting line connected to the detecting transistor.
3. The display device according to claim 2 , wherein the detecting line extends substantially parallel to one of the driving voltage line and the data line.
4. The display device according to claim 1 , wherein the controller comprises a memory storing a table of reference levels that correspond to a range of voltages including the data voltage, and wherein the controller determines a compensation voltage based on a difference between the data voltage that corresponds to a magnitude of the detected electrical signal and a voltage corresponding to the reference level.
5. The display device according to claim 4 , wherein the controller applies the compensation voltage to the data line.
6. The display device according to claim 4 , wherein the controller determines the compensation voltage if the difference is outside a predetermined range of values.
7. The display device according to claim 1 , wherein the electric signal is a measurement of either a voltage or a current.
8. The display device according to claim 1 , wherein the predetermined range comprises an error range in which the detected electric signal is substantially same as the predetermined reference level.
9. A display device comprising:
a pixel electrode;
a detecting transistor detecting a pixel current applied to the pixel electrode; and
a controller regulating a pixel voltage applied to the pixel electrode based on a difference between the pixel current and a predetermined reference level:
wherein the controller comprises a memory storing a table of reference levels including a reference level that corresponds to the pixel current; and
wherein the controller determines a compensation voltage based on a difference between a pixel voltage corresponding to a magnitude of the detected pixel current and a pixel voltage corresponding to the reference level.
10. The display device according to claim 9 , wherein the controller applies the compensation voltage to the pixel electrode.
11. The display device according to claim 9 , wherein the predetermined range comprises an error range in which the detected electric signal is substantially same as the predetermined reference level.
12. A method of controlling a display device, the method comprising:
storing, in a memory, a predetermined reference level corresponding to a data voltage;
turning on a driving transistor;
detecting an electric signal transmitted from the driving transistor to a pixel electrode;
comparing the detected electric signal with the predetermined reference level; and
regulating the data voltage applied to the pixel electrode based on a difference between the electric signal and the predetermined reference level:
wherein regulating the data voltage comprises determining a compensation voltage corresponding to a difference between a data voltage corresponding to a magnitude of the detected electric signal and a voltage that corresponds to the reference level.
13. The method according to claim 12 , further comprising applying the compensation voltage to the pixel electrode.
14. The method according to claim 12 , wherein the electric signal is a measurement of either a voltage or a current.