Picture signal processing circuit, picture signal processing method, and display unit

1. A picture signal processing circuit comprising:

a gamma correction section configured to perform gamma correction on a picture signal;

a gamma modification section configured to provide an offset component to the picture signal that is gamma-corrected by the gamma correction section, the offset component corresponding to at least a light emission duty; and

a measurement section configured to measure a luminance of a light-emitting element of a dummy pixel or a value of a current flowing through the light-emitting element of the dummy pixel, the dummy pixel being provided outside a display region of a display unit, the display unit including at least one pixel that includes a light-emitting element,

the gamma modification section including

an offset component generation section configured to generate the offset component, and

an adder section configured to add the offset component to the picture signal that is gamma-corrected by the gamma correction section, and

the offset component generation section including an offset calculation section configured to calculate the offset component based on a measurement result of the measurement section.

2. The picture signal processing circuit according to claim 1 , wherein the offset component corresponds to the light emission duty and a refresh rate.

3. A picture signal processing method, the method comprising:

preparing a gamma-corrected picture signal;

measuring a luminance of a light-emitting element of a dummy pixel or a value of a current flowing through the light-emitting element of the dummy pixel, the dummy pixel being provided outside a display region of a display unit, the display unit including at least one pixel that includes a light-emitting element; and

providing an offset component corresponding to at least a light emission duty to the gamma-corrected picture signal,

wherein providing the offset component further includes

calculating the offset component based on a result of the measuring of the luminance or the value of the current, and

adding the offset component to the gamma-corrected picture signal that is gamma-corrected.

4. The picture signal processing method according to claim 3 , wherein the offset component corresponds to the light emission duty and a refresh rate.

5. A display unit comprising:

a display including at least one pixel, the at least one pixel comprising a light-emitting element; and

a picture signal processing circuit including

a gamma correction section configured to perform gamma correction on a picture signal,

a gamma modification section configured to provide an offset component to the picture signal that is gamma-corrected by the gamma correction section, the offset component corresponding to at least a light emission duty, and

a measurement section configured to measure a luminance of a light-emitting element of a dummy pixel or a value of a current flowing through the light-emitting element of the dummy pixel, the dummy pixel being provided outside a display region of the display,

the gamma modification section including

an offset component generation section configured to generate the offset component, and

an adder section configured to add the offset component to the picture signal that is gamma-corrected by the gamma correction section, and

the offset component generation section including an offset calculation section configured to calculate the offset component based on a measurement result of the measurement section.

6. The display unit according to claim 5 , wherein the offset component corresponds to the light emission duty and a refresh rate.

7. A picture signal processing circuit comprising:

a gamma correction section configured to perform gamma correction on a picture signal; and

a gamma modification section configured to provide an offset component to the picture signal that is gamma-corrected by the gamma correction section, the offset component corresponding to one or both of a refresh rate and a light emission duty,

the gamma modification section including

an offset component generation section configured to generate the offset component, and

an adder section configured to add the offset component to the picture signal that is gamma-corrected by the gamma correction section, and

the offset component generation section including

a light emission time amount calculation section configured to calculate, based on one or both of the refresh rate and the light emission duty, a light emission time amount of a light-emitting element included in a pixel, and

an offset calculation section configured to calculate, based on the light emission time amount that is calculated by the light emission time amount calculation section, the offset component having an offset amount that is larger as the light emission time amount becomes shorter.

8. The picture signal processing circuit according to claim 7 , wherein the offset calculation section calculates the offset component by determining the offset amount by the following expression:

offset amount=α× Ids 1×( t 1/ t 2−1)

where

t1 is the light emission time amount calculated by the light emission time amount calculation section in a first operation,

t2 is the light emission time amount calculated by the light emission time amount calculation section in a second operation that is different from the first operation in one or both of the refresh rate and the light emission duty,

Ids1 is a value of a current upon light emission that flows through a drive transistor in the first operation, the drive transistor driving the light-emitting element,

α is a predetermined constant, and

the offset amount is the offset component in the second operation that is changed from the first operation.

9. A picture signal processing method comprising:

preparing a gamma-corrected picture signal; and

providing an offset component corresponding to one or both of a refresh rate and a light emission duty, to the gamma-corrected picture signal,

wherein providing the offset component includes

calculating, based on one or both of the refresh rate and the light emission duty, a light emission time amount of a light-emitting element included in a pixel,

calculating, based on the light emission time amount that is calculated, the offset component having an offset amount that is larger as the light emission time amount becomes shorter, and

adding the offset component to the gamma-corrected picture signal that is gamma-corrected.

10. The picture signal processing method according to claim 9 , wherein the calculating the offset component determines the offset amount by the following expression:

offset amount=α× Ids 1×( t 1/ t 2−1)

where

t1 is the light emission time amount calculated in a first operation,

t2 is the light emission time amount calculated in a second operation that is different from the first operation in one or both of the refresh rate and the light emission duty,

Ids1 is a value of a current upon light emission that flows through a drive transistor in the first operation, the drive transistor driving the light-emitting element,

α is a predetermined constant, and

the offset amount is the offset component in the second operation that is changed from the first operation.

11. A display unit comprising:

a display including at least one pixel, the at least one pixel comprising a light-emitting element and a drive transistor that drives the light-emitting element; and

a picture signal processing circuit including

a gamma correction section configured to perform gamma correction on a picture signal, and

a gamma modification section configured to provide an offset component to the picture signal that is gamma-corrected by the gamma correction section, the offset component corresponding to one or both of a refresh rate and a light emission duty,

the gamma modification section including

an offset component generation section configured to generate the offset component, and

an adder section configured to add the offset component to the picture signal that is gamma-corrected by the gamma correction section, and

the offset component generation section including

a light emission time amount calculation section configured to calculate, based on one or both of the refresh rate and the light emission duty, a light emission time amount of the light-emitting element, and

an offset calculation section configured to calculate, based on the light emission time amount that is calculated by the light emission time amount calculation section, the offset component having an offset amount that is larger as the light emission time amount becomes shorter.

12. The display unit according to claim 11 , wherein the offset calculation section calculates the offset component by determining the offset amount by the following expression:

offset amount=α× Ids 1×( t 1/ t 2−1)

where

t1 is the light emission time amount calculated by the light emission time amount calculation section in a first operation,

t2 is the light emission time amount calculated by the light emission time amount calculation section in a second operation that is different from the first operation in one or both of the refresh rate and the light emission duty,

Ids1 is a value of a current upon light emission that flows through the drive transistor in the first operation, the drive transistor driving the light-emitting element,

α is a predetermined constant, and

the offset amount is the offset component in the second operation that is changed from the first operation.