Display device, method for driving the same, and electronic device
View Patent ↗A display device including a display unit including first and second lines, light emitting elements and pixel circuits; a first drive unit sequentially applying a selection pulse to the first lines; and a second drive unit applying a signal pulse including first to third voltages to each of the second lines. Each of the pixel circuits includes a first transistor sampling the signal pulse, and a second transistor driving one of the light emitting elements. The first drive unit applies the selection pulse when the first voltage is being applied by the second drive unit, before a correction of a threshold voltage of the second transistor is initiated and within a period that the one of the light emitting elements is being turned out, and the first drive unit applies the selection pulse when the second voltage is being applied by the second drive unit.
1. A display device comprising a display unit including:
a plurality of light emitting elements; and
a plurality of pixel driving circuits, each of the pixel driving circuits including a drive transistor configured to provide a driving current to a corresponding one of the light emitting elements such luminance intensity of the light emitting element is dependent on a luminance signal,
wherein, each of the pixel driving circuit is driven such that
(a) an anode electrode of the driving transistor is sequentially set to a first potential, a second potential, and a third potential,
(b) the first potential is higher than the second potential, and the third potential is a potential which causes the light emitting element to emit light based on the luminance signal,
(c) the first potential is supplied before a preparation period for light emission and within a period in which the light emitting element is turned off, and
(d) a difference between the first potential and the second potential is large enough to reduce a probability of occurrence of breakdown on the light emitting element.
2. The display device according to claim 1 , wherein a cathode electrode of the light emitting element is set to a cathode potential which is not higher than the first potential.
3. The display device according to claim 2 , wherein the light emitting element is set in a reverse-biased state in the preparation period.
4. The display device according to claim 2 , wherein each of the pixel driving circuits is driven such that a threshold correction operation for the driving transistor is executed during the preparation period.
5. The display device according to claim 1 , wherein an application period of the first potential is longer than the preparation period during which the second potential is applied to the anode electrode.
6. The display device according to claim 5 , wherein a difference between length of the application period and length of the preparation period is large enough to reduce the probability of occurrence of breakdown on the light emitting element.
7. The display device according to claim 1 , wherein:
each of the pixel driving circuits further includes a sampling transistor configured to sample a signal potential based on the luminance signal,
and wherein the anode electrode of the driving transistor is sequentially set to the first potential, the second potential and the third potential based on potentials provided for a control node of the drive transistor via the sampling transistor.
8. The display device according to claim 7 , wherein each of the pixel driving circuits further includes a capacitor configured to store a voltage based on the luminance signal, the capacitor being connected between the anode electrode and the sampling transistor so as to reflect the potentials provided via the sampling transistor to the potential of the anode electrode.
9. The display device according to claim 1 , wherein each of the light emitting elements includes an organic EL element.
10. The display device according to claim 1 , wherein the light emitting elements includes a first light emitting element configured to emit light of a first color and a second light emitting element configured to emit light of a second color which is different from the first color.
11. A light emitting device including:
a light emitting element; and
a driving circuit including a drive transistor configured to provide a driving current to the light emitting element such that luminance intensity of the light emitting element is dependent on a luminance signal,
wherein, the driving circuit is driven such that
(a) an anode electrode of the driving transistor is sequentially set to a first potential, a second potential, and a third potential,
(b) the first potential is higher than the second potential, and the third potential is a potential which causes the light emitting element to emit light based on the luminance signal,
(c) the first potential is supplied before a preparation period for light emission and within a period in which the light emitting element is turned off, and
(d) a difference between the first potential and the second potential is large enough to reduce a probability of occurrence of breakdown on the light emitting element.
12. The light emitting device according to claim 11 , wherein a cathode electrode of the light emitting element is set to a cathode potential which is not higher than the first potential.
13. The light emitting device according to claim 12 , wherein the light emitting element is set in a reverse-biased state in the preparation period.
14. The light emitting device according to claim 12 , wherein the driving circuit is driven such that a threshold correction operation for the driving transistor is executed during the preparation period.
15. The light emitting device according to claim 11 , wherein an application period of the first potential is longer than the preparation period during which the second potential is applied to the anode electrode.
16. The light emitting device according to claim 15 , wherein a difference between length of the application period and length of the preparation period is large enough to reduce the probability of occurrence of breakdown on the light emitting element.
17. The light emitting device according to claim 11 , wherein,
the driving circuit further includes a sampling transistor configured to sample a signal potential based on the luminance signal,
and wherein the anode electrode of the driving transistor is sequentially set to the first potential, the second potential and the third potential based on potentials provided via the sampling transistor.
18. The light emitting device according to claim 17 , wherein,
the driving circuits further include a capacitor configured to store a voltage based on the luminance signal,
and wherein the capacitor is connected between the anode electrode and the sampling transistor so as to reflect the potentials provided via the sampling transistor to the potential of the anode electrode.
19. The light emitting device according to claim 11 , wherein the light emitting element includes an organic EL element.
20. An electronic device comprising a plurality of the light emitting devices according to claim 11 .
21. The electronic device according to claim 20 , wherein each of the light emitting devices is configured to emit light of different colors each other.
22. The electronic device according to claim 20 , wherein the light emitting devices are arranged in a matrix form.