Display device

1. A display device comprising:

display emissive elements arranged in a matrix within a display region for emitting light in accordance with a drive current;

a measurement emissive element which is formed in a position different from the display region and formed by the same process as the organic EL elements formed in the display region;

a drive voltage supply circuit for supplying drive voltage to the measurement emissive element;

a drive state detection circuit for detecting a drive state of the measurement emissive element in the case where the drive voltage is supplied by the drive voltage supply circuit; and

a correction circuit for correcting voltage to be applied to each display emissive element in the display region based on the drive state detected by the drive state detection circuit;

wherein the drive voltage to be supplied to the display emissive elements in the display region is a specified voltage and the drive of the display emissive elements in the display region is a digital drive where the drive voltage to be supplied to the measurement emissive element is a predetermined voltage and the supply time of the drive voltage is controllable; and

the correction circuit changes positive or negative power supply voltage of the display emissive elements in the display region.

2. The display device according to claim 1 wherein:

the drive state detection circuit detects the drive current flowing in the measurement emissive element.

3. The display device according to claim 1 wherein:

the drive state detection circuit detects the emission amount of the measurement emissive element.

4. The display device according to claim 1 wherein:

the drive voltage supply circuit supplies drive voltage, which represents the drive voltage supplied to the display emissive elements in the display region, to the measurement emissive element for measurement purposes.

5. The display device according to claim 4 wherein:

the drive voltage supply circuit supplies typical pulsed voltage, which digitally drives the display emissive elements in the display region, to the measurement emissive element.

6. The display device according to claim 1 wherein:

the drive voltage supply circuit detects the degradation over time of the display emissive elements in the display region based on a detection value of the drive state detect circuit by continuously supplying drive voltage, which is same as the voltage to the display emissive elements in the display region, to the measurement emissive element.

7. The display device according to claim 1 wherein:

the display emissive elements in the display region and the measurement emissive elements have the three colors of red (R), green (G) and blue (B), and

the display device comprises a display data set circuit that calculates the maximum luminance of each color of RGB from the drive state of the measurement emissive element of each color of RGB, which is detected by the drive state detect circuit, in the drive state detection circuit and sets display data within a range where the white color is executable.

8. The display device according to claim 1 wherein:

the display emissive elements in the display region and the measurement emissive element are organic EL elements.

9. A method of displaying pixels with a predetermined white balance in a display region emitting light in accordance with a drive current, the display method comprising the steps of:

setting an initialization value of a power source line when a display is turned on;

measuring a current of a plurality of measurement pixels;

calculating a maximum luminance based on the measured current of the measurement pixels;

determining whether calculated value of the maximum luminance is within a targeted range of a set luminance;

resetting the value of the power source line positively if the maximum luminance is greater than the targeted range, and negatively if the maximum luminance is less than the targeted range, and repeating the first four steps above;

setting a maximum gradation of display pixels achieving the predetermined white balance for the display if the calculated value of the maximum luminance is within the targeted range; and

setting a display data of display pixels for the display.

10. The method according to claim 9 , wherein the targeted range is ±10% of the set luminance.

11. A method of displaying pixels with a predetermined white balance in a display region emitting light in accordance with a luminance emission, the display method comprising the steps of:

setting an initialization value of a power source line when a display is turned on;

measuring the luminance emission of a plurality of measurement pixels;

calculating a maximum luminance based on the measured luminance emission of the measurement pixels;

determining whether calculated value of the maximum luminance is within a targeted range of a set luminance;

resetting the value of the power source line positively if the maximum luminance is greater than the targeted range, and negatively if the maximum luminance is less than the targeted range, and repeating the first four steps above;

setting a maximum gradation of display pixels achieving the predetermined white balance for the display if the calculated value of the maximum luminance is within the targeted range; and

setting a display data of display pixels for the display.

12. The method according to claim 11 , wherein the targeted range is ±10% of the set luminance.