Display device
A display device includes a display area including a plurality of pixels arrayed next to one another in a first direction and in a second direction that is different from the first direction, and a control circuit, wherein each of the pixels includes a light-emitting element configured to emit light by a current flowing therethrough, a drive transistor, a shut-off transistor, and a holding capacitance.
1. A display device comprising:
a display area including a plurality of pixels arrayed next to one another in a first direction and in a second direction that is different from the first direction; and
a control circuit, wherein
each of the pixels includes
a light-emitting element configured to emit light by a current flowing therethrough,
a drive transistor,
a shut-off transistor, and
a holding capacitance,
while one terminal of the light-emitting element is coupled to one of a source and a drain of the drive transistor, a first potential is supplied to the other terminal of the light-emitting element,
a second potential that is higher than the first potential is supplied to the other one of the source and the drain of the drive transistor via the shut-off transistor,
the shut-off transistor supplies or shuts off the second potential to the drive transistor,
the holding capacitance is coupled between the source and a gate of the drive transistor, and
the control circuit
controls the shut-off transistor to have the shut-off transistor on, thereby supplying the second potential to the drive transistor and writing an initialization potential into the gate of the drive transistor,
thereafter controls the shut-off transistor to have the shut-off transistor off, thereby shutting off supply of the second potential,
writes a video writing potential resulting from a video signal into the gate of the drive transistor, and
sets the initialization potential in a manner such that, as a luminance set value for luminance of the video signal is smaller, a potential difference between the source and the gate of the drive transistor is larger, wherein a video amplitude rate is set to be at least 80% where the luminance set value is in a low range of a plurality of set ranges for the luminance set value partitioned by a plurality of thresholds, the low range corresponding to a lowest threshold of the plurality of set ranges, and wherein the video amplitude rate is a proportion of the amplitude of the video writing potential after reflection of the luminance set value to the amplitude of the video writing potential before the reflection of the luminance set value as the luminance set value,
wherein the control circuit
is provided with an emission period and a non-emission period within an emission-enabled period that starts after the video writing potential is supplied to the gate of the drive transistor, the emission period being a period for which the light-emitting element is caused to emit light with an intensity corresponding to the video writing potential, the non-emission period being a period for which a current is forced to stop being supplied to the light-emitting element, the emission-enabled period being a period for which the light-emitting element is enabled to emit light,
in the emission period, controls the shut-off transistor to have the shut-off transistor on and thereby supplies the second potential,
in the non-emission period, controls the shut-off transistor to have the shut-off transistor off and thereby shuts off supply of the second potential, and
sets a larger value as a proportion of the non-emission period to the emission-enabled period as the luminance set value is smaller,
wherein the control circuit
has a threshold set for the luminance set value, and
sets the initialization potential in a manner such that a second potential difference between the source and the gate of the drive transistor exceeds a first potential difference between the source and the gate of the drive transistor, the first potential difference being generated by the initialization potential to be written into the gate of the drive transistor when the luminance set value is larger than the threshold, the second potential difference being generated by the initialization potential to be written into the gate of the drive transistor when the luminance set value is not larger than the threshold, and
wherein the control circuit sets a second proportion larger than a first proportion, the first proportion being the proportion of the non-emission period to the emission-enabled period to be applied when the luminance set value is larger than the threshold, the second proportion being the proportion of the non-emission period to the emission-enabled period to be applied when the luminance set value is not larger than the threshold.
2. The display device according to claim 1 , wherein the control circuit
is provided with the plurality of set ranges for the luminance set value that are partitioned by the plurality of the thresholds, and
sets different values as the initialization potential to be written into the gate of the drive transistor of the pixel when the luminance set value is in the respective set ranges.
3. The display device according to claim 1 , wherein the control circuit includes a storage circuit configured to store therein initialization voltage information that has a defined correspondence relation between the initialization potential and the luminance set value.
4. The display device according to claim 3 , wherein the storage circuit stores therein black-insertion rate information that has a defined correspondence relation between the proportion of the non-emission period to the emission-enabled period and the luminance set value.
5. The display device according to claim 1 , wherein the display area comprises:
a plurality of first signal lines configured to supply the video writing potential to the gates of the drive transistors of the pixels that are arrayed next to one another in the second direction; and
a plurality of second signal lines configured to supply the initialization potential to the gates of the drive transistors of the pixels that are arrayed next to one another in the second direction.
6. A display device comprising:
a display area including a plurality of pixels arrayed next to one another in a first direction and in a second direction that is different from the first direction; and
a control circuit, wherein
each of the pixels includes
a light-emitting element configured to emit light by a current flowing therethrough,
a drive transistor,
a shut-off transistor, and
a holding capacitance,
while one terminal of the light-emitting element is coupled to one of a source and a drain of the drive transistor, a first potential is supplied to the other terminal of the light-emitting element,
a second potential that is higher than the first potential is supplied to the other one of the source and the drain of the drive transistor via the shut-off transistor,
the shut-off transistor supplies or shuts off the second potential to the drive transistor,
the holding capacitance is coupled between the source and a gate of the drive transistor, and
the control circuit
controls the shut-off transistor to have the shut-off transistor on, thereby supplying the second potential to the drive transistor and writing an initialization potential into the gate of the drive transistor,
thereafter controls the shut-off transistor to have the shut-off transistor off, thereby shutting off supply of the second potential,
writes a video writing potential resulting from a video signal into the gate of the drive transistor, and
sets the initialization potential in a manner such that, as a luminance set value for luminance of the video signal is smaller, a potential difference between the source and the gate of the drive transistor is larger, wherein a video amplitude rate is set to be at least 80% where the luminance set value is in a low range of a plurality of set ranges for the luminance set value partitioned by a plurality of thresholds, the low range corresponding to a lowest threshold of the plurality of set ranges, and wherein the video amplitude rate is a proportion of the amplitude of the video writing potential after reflection of the luminance set value to the amplitude of the video writing potential before the reflection of the luminance set value as the luminance set value,
wherein the control circuit
is provided with an emission period and a non-emission period within an emission-enabled period that starts after the video writing potential is supplied to the gate of the drive transistor, the emission period being a period for which the light-emitting element is caused to emit light with an intensity corresponding to the video writing potential, the non-emission period being a period for which a current is forced to stop being supplied to the light-emitting element, the emission-enabled period being a period for which the light-emitting element is enabled to emit light,
in the emission period, controls the shut-off transistor to have the shut-off transistor on and thereby supplies the second potential,
in the non-emission period, controls the shut-off transistor to have the shut-off transistor off and thereby shuts off supply of the second potential, and
sets a larger value as a proportion of the non-emission period to the emission-enabled period as the luminance set value is smaller,
wherein the control circuit
has a threshold set for the luminance set value, and
sets the initialization potential in a manner such that a second potential difference between the source and the gate of the drive transistor exceeds a first potential difference between the source and the gate of the drive transistor, the first potential difference being generated by the initialization potential to be written into the gate of the drive transistor when the luminance set value is larger than the threshold, the second potential difference being generated by the initialization potential to be written into the gate of the drive transistor when the luminance set value is not larger than the threshold, and
wherein the control circuit sets different values as the proportion of the non-emission period to the emission-enabled period when the luminance set value is in the respective set ranges.
7. The display device according to claim 6 , wherein the control circuit includes a storage circuit configured to store therein initialization voltage information that has a defined correspondence relation between the initialization potential and the luminance set value.
8. The display device according to claim 7 , wherein the storage circuit stores therein black-insertion rate information that has a defined correspondence relation between the proportion of the non-emission period to the emission-enabled period and the luminance set value.
9. The display device according to claim 6 , wherein the display area comprises:
a plurality of first signal lines configured to supply the video writing potential to the gates of the drive transistors of the pixels that are arrayed next to one another in the second direction; and
a plurality of second signal lines configured to supply the initialization potential to the gates of the drive transistors of the pixels that are arrayed next to one another in the second direction.
10. A display device comprising:
a display area including a plurality of pixels arrayed next to one another in a first direction and in a second direction that is different from the first direction; and
a control circuit, wherein
each of the pixels includes
a light-emitting element configured to emit light by a current flowing therethrough,
a drive transistor,
a shut-off transistor, and
a holding capacitance,
while one terminal of the light-emitting element is coupled to one of a source and a drain of the drive transistor, a first potential is supplied to the other terminal of the light-emitting element,
a second potential that is higher than the first potential is supplied to the other one of the source and the drain of the drive transistor via the shut-off transistor,
the shut-off transistor supplies or shuts off the second potential to the drive transistor,
the holding capacitance is coupled between the source and a gate of the drive transistor, and
the control circuit
controls the shut-off transistor to have the shut-off transistor on, thereby supplying the second potential to the drive transistor and writing an initialization potential into the gate of the drive transistor,
thereafter controls the shut-off transistor to have the shut-off transistor off, thereby shutting off supply of the second potential,
writes a video writing potential resulting from a video signal into the gate of the drive transistor, and
sets the initialization potential in a manner such that, as a luminance set value for luminance of the video signal is smaller, a potential difference between the source and the gate of the drive transistor is larger, wherein a video amplitude rate is set to be at least 80% where the luminance set value is in a low range of a plurality of set ranges for the luminance set value partitioned by a plurality of thresholds, the low range corresponding to a lowest threshold of the plurality of set ranges, and wherein the video amplitude rate is a proportion of the amplitude of the video writing potential after reflection of the luminance set value to the amplitude of the video writing potential before the reflection of the luminance set value as the luminance set value,
wherein the control circuit
is provided with an emission period and a non-emission period within an emission-enabled period that starts after the video writing potential is supplied to the gate of the drive transistor, the emission period being a period for which the light-emitting element is caused to emit light with an intensity corresponding to the video writing potential, the non-emission period being a period for which a current is forced to stop being supplied to the light-emitting element, the emission-enabled period being a period for which the light-emitting element is enabled to emit light,
in the emission period, controls the shut-off transistor to have the shut-off transistor on and thereby supplies the second potential,
in the non-emission period, controls the shut-off transistor to have the shut-off transistor off and thereby shuts off supply of the second potential, and
sets a larger value as a proportion of the non-emission period to the emission-enabled period as the luminance set value is smaller,
wherein the control circuit
has a threshold set for the luminance set value, and
sets the initialization potential in a manner such that a second potential difference between the source and the gate of the drive transistor exceeds a first potential difference between the source and the gate of the drive transistor, the first potential difference being generated by the initialization potential to be written into the gate of the drive transistor when the luminance set value is larger than the threshold, the second potential difference being generated by the initialization potential to be written into the gate of the drive transistor when the luminance set value is not larger than the threshold, and
wherein the control circuit sets a smaller value as the proportion of the amplitude of the video writing potential after reflection of the luminance set value to the amplitude of the video writing potential before the reflection of the luminance set value as the luminance set value is smaller within each of the plurality of set ranges.
11. The display device according to claim 10 , wherein the storage circuit stores therein video amplitude rate information that has a defined correspondence relation between the proportion of the amplitude of the video writing potential after the reflection of the luminance set value to the amplitude of the video writing potential before the reflection of the luminance set value and the luminance set value.
12. The display device according to claim 10 , wherein the control circuit includes a storage circuit configured to store therein initialization voltage information that has a defined correspondence relation between the initialization potential and the luminance set value.
13. The display device according to claim 12 , wherein the storage circuit stores therein black-insertion rate information that has a defined correspondence relation between the proportion of the non-emission period to the emission-enabled period and the luminance set value.
14. The display device according to claim 10 , wherein the display area comprises:
a plurality of first signal lines configured to supply the video writing potential to the gates of the drive transistors of the pixels that are arrayed next to one another in the second direction; and
a plurality of second signal lines configured to supply the initialization potential to the gates of the drive transistors of the pixels that are arrayed next to one another in the second direction.