Display device and method for driving display device
View Patent ↗A method for driving a display device that includes a display unit and is driven by a sequence of row-by-row sequential scanning that includes a vertical blanking period, the display unit having pixels arranged in rows and columns, each pixel including an anode formed on a drive circuit layer, an organic light emitting layer formed above the anode and including a light emitting substance, and a transparent cathode formed above the organic light emitting layer, the method includes initializing a circuit element, writing a signal voltage to a capacitive element, inserting a black display to display the black display during a period determined based on a resistance value of the transparent cathode, and causing the organic EL element to emit light.
1. A method for driving a display device that includes a display unit and is driven by a sequence of row-by-row sequential scanning that includes a vertical blanking period, the display unit having pixels arranged in rows and columns, each of the pixels including a first electrode formed on a drive circuit substrate on which a circuit element is formed, a light emitting layer formed above the first electrode and including a light emitting substance, and a second electrode formed above the light emitting layer,
the method comprising:
initializing a light emitting element and the circuit element;
writing a signal voltage to the circuit element after the initializing;
inserting, after the writing, a black display to display the black display without causing the light emitting element to emit light during a first period that is determined based on a resistance value of the second electrode; and
causing the light emitting element to emit light after the inserting.
2. The method for driving a display device according to claim 1 ,
wherein, in the inserting, the first period is set shorter as the resistance value of the second electrode increases, when the black display is displayed without the light emitting element being caused to emit light.
3. The method for driving a display device according claim 1 ,
wherein, in the inserting, the first period is determined to satisfy a relation of:
T 1≥−0.150 R+ 148.69
where R (Ω/sq.) is a sheet resistance of the second electrode, 1H is a unit horizontal scanning period in the row-by-row sequential scanning, and T1 (H) is the first period.
4. The method for driving a display device according to claim 1 ,
wherein, in the light emitting, potentials of the second electrodes of pixels in an uppermost row of the display unit fluctuate at a light-emission start timing in the uppermost row of the display unit, and
in the initializing, an initialization completion timing in a pixel row that is located a predetermined number of pixel rows below the uppermost row of the display unit coincides with the light-emission start timing in the uppermost row of the display unit.
5. The method for driving a display device according to claim 1 ,
wherein the initializing is implemented during a second period that is determined based on a resistance value of the second electrode.
6. The method for driving a display device according to claim 5 ,
wherein the initializing is implemented while the second period is set shorter as the resistance value of the second electrode increases.
7. The method for driving a display device according to claim 5 ,
wherein, in the initializing, the second period is determined to satisfy a relation of:
T 2≥−0.0552 R+ 139.05
where R (Ω/sq.) is a sheet resistance of the second electrode, 1H is a unit horizontal scanning period in the row-by-row sequential scanning, and T2 (H) is the second period.
8. A method for driving a display device that includes a display unit and is driven by a sequence of row-by-row sequential scanning that includes a vertical blanking period, the display unit having pixels arranged in rows and columns, each of the pixels including a first electrode formed on a drive circuit substrate on which a circuit element is formed, a light emitting layer formed above the first electrode and including a light emitting substance, and a second electrode formed above the light emitting layer,
the method comprising:
initializing a light emitting element and the circuit element during a second period that is determined based on a resistance value of the second electrode;
writing a signal voltage to the circuit element after the initializing; and
causing the light emitting element to emit light after the writing.
9. The method for driving a display device according to claim 8 ,
wherein, in the initializing, the light emitting element and the circuit element are initialized while the second period is set shorter as the resistance value of the second electrode increases.
10. The method for driving display device according to claim 8 ,
wherein, in the initializing, the second period is determined to satisfy a relation of:
T 2≥−0.0552 R+ 139.05
where R (Ω/sq.) is a sheet resistance of the second electrode, 1H is a unit horizontal scanning period in the row-by-row sequential scanning, and T2 (H) is the second period.
11. The method for driving a display device according to claim 8 ,
wherein, in the initializing, potentials of the second electrodes of pixels in a lowermost row of the display unit fluctuate at an initialization timing in the lowermost row of the display unit, and
in the writing, a write completion timing in a pixel row that is located a predetermined number of pixel rows above the lowermost row of the display unit coincides with the initialization timing in the lowermost row of the display unit.
12. A display device comprising a display unit and being driven by a sequence of row-by-row sequential scanning that includes a vertical blanking period, the display unit having pixels arranged in rows and columns, each of the pixels including a light emitting element and a circuit element for driving light emission of the light emitting element,
the pixel including:
a first electrode formed on a drive circuit substrate on which the circuit element is formed;
a light emitting layer formed above the first electrode and including a light emitting substance; and
a second electrode formed above the light emitting layer,
the display device further comprising
a control unit configured to execute:
applying an initialization voltage to the first electrode;
writing a signal voltage to the circuit element after the initializing;
inserting, after the writing, a black display to display the black display without causing the light emitting element to emit light during a first period that is determined based on a resistance value of the second electrode; and
causing the light emitting element to emit light after the inserting.
13. The display device according to claim 12 ,
wherein the pixel further includes:
an auxiliary line formed on the drive circuit substrate and spaced from the first electrode; and
an intermediate layer disposed between the first electrode and the second electrode, and
the intermediate layer and the second electrode extend from above the first electrode to above the auxiliary line.
14. The display device according to claim 12 ,
wherein the control unit is configured to, in the inserting, determine the first period to satisfy a relation:
T 1≥−0.150 R+ 148.69
where R (Ω/sq.) is a sheet resistance of the second electrode, 1H is a unit horizontal scanning period in the row-by-row sequential scanning, and T1 (H) is the first period.
15. The display device according to claim 12 ,
wherein the control unit is configured to implement the initializing during a second period that is determined based on a resistance value of the second electrode.
16. The display device according to claim 15 ,
wherein the control unit is configured to, in the initializing, determine the second period to satisfy a relation of:
T 2≥−0.0552 R+ 139.05
where R (Ω/sq.) is a sheet resistance of the second electrode, 1H is a unit horizontal scanning period in the row-by-row sequential scanning, and T2 (H) is the second period.
17. A display device comprising a display unit and being driven by a sequence of row-by-row sequential scanning that includes a vertical blanking period, the display unit having pixels arranged in rows and columns, each of the pixels including a light emitting element and a circuit element for driving light emission of the light emitting element,
the pixel including:
a first electrode formed on a drive circuit substrate on which the circuit element is formed;
a light emitting layer formed above the first electrode and including a light emitting substance; and
a second electrode formed above the light emitting layer,
the display device further comprising
a control unit configured to execute:
applying an initialization voltage to the first electrode during a second period that is determined based on a resistance value of the second electrode;
writing a signal voltage to the circuit element after the initializing; and
causing the light emitting element to emit light after the writing.
18. The display device according to claim 17 ,
wherein the pixel further includes:
an auxiliary line formed on the drive circuit substrate and spaced from the first electrode; and
an intermediate layer disposed between the first electrode and the second electrode, and
the intermediate layer and the second electrode extend from above the first electrode to above the auxiliary line.
19. The display device according to claim 17 ,
wherein the control unit is configured to, in the initializing, determine the second period to satisfy a relation of:
T 2≥−0.0552 R+ 139.05
where R (Ω/sq.) is a sheet resistance of the second electrode, 1H is a unit horizontal scanning period in the row-by-row sequential scanning, and T2 (H) is the second period.