DISPLAY DEVICE AND EPITAXIAL WAFER

1 . A display device, comprising:

a display substrate; and

a plurality of pixel units, comprising:

a first pixel unit located on the display substrate and comprising a first sub pixel unit having a first luminous area; and

a second pixel unit located on the display substrate and comprising a second sub pixel unit having a second luminous area,

wherein the first sub pixel unit and the second sub pixel unit belong to the same color type;

the first sub pixel unit and the second sub pixel unit are formed from a same epitaxial wafer and then transferred to the display substrate; and

the first luminous area and the second luminous area are different and are related to a photoluminescence measurement result of the epitaxial wafer.

2 . The display device according to claim 1 , wherein the photoluminescence measurement result comprises a measured peak wavelength distribution; there is a plurality of measured positions on the epitaxial wafer; the first sub pixel unit, before being formed from the epitaxial wafer, corresponds to one measured position among the plurality of measured positions; the second sub pixel unit, before being formed from the epitaxial wafer, corresponds to another measured position among the plurality of measured positions; the measured peak wavelength distribution indicates a plurality of measured peak wavelengths respectively related to the plurality of measured positions; the first luminous area of the first sub pixel unit is related to the measured peak wavelength of the measured position corresponding to the first sub pixel unit; and the second luminous area of the second sub pixel unit is related to the measured peak wavelength of the measured position corresponding to the second sub pixel unit.

3 . The display device according to claim 2 , wherein, when the measured peak wavelength corresponding to the first sub pixel unit is larger than an upper limitation of a reference wavelength range, the first luminous area of the first sub pixel unit is determined as smaller than a standard area; and when the measured peak wavelength corresponding to the first sub pixel unit is shorter than a lower limitation of the reference wavelength range, the first luminous area of the first sub pixel unit is determined as larger than the standard area; and when the measured peak wavelength corresponding to the second sub pixel unit is larger than an upper limitation of a reference wavelength range, the second luminous area of the second sub pixel unit is determined as smaller than a standard area; and when the measured peak wavelength corresponding to the second sub pixel unit is shorter than a lower limitation of the reference wavelength range, the second luminous area of the second sub pixel unit is determined as larger than the standard area.

4 . The display device according to claim 3 , wherein the first sub pixel unit is controlled by a driving current to generate first emitted light, the second sub pixel unit is controlled by the driving current to generate second emitted light, and a difference between the peak wavelength of the first emitted light and the peak wavelength of the second emitted light is less than a first predetermined threshold.

5 . The display device according to claim 4 , wherein the first predetermined threshold is not larger than 2 nm.

6 . The display device according to claim 4 , wherein a current density of the first sub pixel unit and a current density of the second sub pixel unit range from 0.001 A/cm 2 to 5 A/cm 2 .

7 . (canceled)

8 . The display device according to claim 1 , wherein each of the plurality of pixel units comprises at least three different color types of sub pixel units; and in the same direction, every two adjacent sub pixel units of the same color, among the pixel units, have a substantially same distance therebetween.

9 . The display device according to claim 1 , wherein a relative location of the first and second sub pixel units before being formed from the epitaxial wafer is substantially equal to a relative location of the first and second sub pixel units on the display substrate.

10 . (canceled)

11 . (canceled)

12 . (canceled)

13 . The display device according to claim 1 , wherein the photoluminescence measurement result of the epitaxial wafer comprises a standard peak wavelength range, the measured peak wavelength of the first sub pixel unit is in the standard peak wavelength range, and the measured peak wavelength of the second sub pixel unit exceeds the standard peak wavelength range.

14 . The display device according to claim 13 , wherein when the measured peak wavelength of the second sub pixel unit is larger than measured peak wavelengths in the standard peak wavelength range, the luminous area of the second sub pixel unit is smaller than the luminous area of the first sub pixel unit; and when the measured peak wavelength of the second sub pixel unit is less than the measured peak wavelengths in the standard peak wavelength range, the luminous area of the second sub pixel unit is larger than the luminous area of the first sub pixel unit.