Display panel and display device

1. A display panel, comprising:

a substrate;

at least three different light-emitting units disposed on the substrate and emitting at least three different colors; and

at least three buffer encapsulation layers disposed on a side of the at least three different light-emitting units facing away from the substrate, wherein the at least three buffer encapsulation layers are in one-to-one correspondence with the at least three different light-emitting units, a thickness of at least one buffer encapsulation layer corresponding to at least one light-emitting unit among the at least three different light-emitting units is different from respective thicknesses of the other buffer encapsulation layers corresponding to the other light-emitting units among the at least three different light-emitting units, and thicknesses of cathode layer of the at least three different light-emitting units vary in proportion to rates at which brightness of light emitted from each light-emitting unit decays.

2. The display panel of claim 1 , further comprising:

a plurality of light extraction layers disposed on one side of the at least three buffer encapsulation layers adjacent to the at least three different light-emitting units; wherein a thickness of at least one light extraction layer corresponding to at least one light-emitting unit among the at least three different light-emitting units is different from respective thicknesses of the other light extraction layers corresponding to the other light-emitting units among the at least three different light-emitting units.

3. The display panel of claim 2 , wherein the at least three different light-emitting units comprise a first light-emitting unit, a second light-emitting unit, and a third light-emitting unit; wherein a wavelength of light emitted from the first light-emitting unit is greater than a wavelength of light emitted from the second light-emitting unit, and the wavelength of the light emitted from the second light-emitting unit is greater than a wavelength of light emitted from the third light-emitting unit.

4. The display panel of claim 3 , wherein as a viewing angle increases in a range, a rate at which a brightness of the light emitted from the first light-emitting unit decays is greater than a rate at which a brightness of the light emitted from the second light-emitting unit decays and a rate at which a brightness of the light emitted from the third light-emitting unit decays respectively, and a thickness of a buffer encapsulation layer corresponding to the first light-emitting unit is greater than a thickness of a buffer encapsulation layer corresponding to the second light-emitting unit and a thickness of a buffer encapsulation layer corresponding to the third light-emitting unit respectively.

5. The display panel of claim 3 , wherein as a viewing angle increases in a range, a rate at which a brightness of the light emitted from the second light-emitting unit decays is greater than a rate at which a brightness of the light emitted from the first light-emitting unit decays and a rate at which a brightness of the light emitted from the third light-emitting unit decays respectively, and a thickness of a buffer encapsulation layer corresponding to the second light-emitting unit is less than a thickness of a buffer encapsulation layer corresponding to the first light-emitting unit and a thickness of a buffer encapsulation layer corresponding to the third light-emitting unit respectively.

6. The display panel of claim 3 , wherein as a viewing angle increases in a range, a rate at which a brightness of the light emitted from the third light-emitting unit decays is greater than a rate at which a brightness of the light emitted from the first light-emitting unit decays and a rate at which a brightness of the light emitted from the second light-emitting unit decays respectively, and a thickness of a buffer encapsulation layer corresponding to the third light-emitting unit is greater than a thickness of a buffer encapsulation layer corresponding to the first light-emitting unit and a thickness of a buffer encapsulation layer corresponding to the second light-emitting unit respectively.

7. The display panel of claim 4 , wherein a thickness of a light extraction layer corresponding to the first light-emitting unit is less than a thickness of a light extraction layer corresponding to the second light-emitting unit and a thickness of a light extraction layer corresponding to the third light-emitting unit respectively.

8. The display panel of claim 4 , wherein a thickness of a light extraction layer corresponding to the second light-emitting unit is less than a thickness of a light extraction layer corresponding to the first light-emitting unit and a thickness of a light extraction layer corresponding to the third light-emitting unit, respectively.

9. The display panel of claim 4 , wherein a thickness of a light extraction layer corresponding to the third light-emitting unit is greater than a thickness of a light extraction layer corresponding to the first light-emitting unit and a thickness of a light extraction layer corresponding to the second light-emitting unit respectively.

10. The display panel of claim 1 , wherein a material of one of the at least three buffer encapsulation layers comprises lithium fluoride (LiF) or calcium fluoride (CaF2).

11. The display panel of claim 3 , wherein one of the at least three different light-emitting units comprises an anode, a light-emitting layer, and a cathode layer.

12. A display panel comprising:

a substrate;

at least three different light-emitting units disposed on the substrate and emitting at least three different colors; and

at least three buffer encapsulation layers disposed on a side of the at least three different light-emitting units facing away from the substrate, wherein the at least three buffer encapsulation layers are in one-to-one correspondence with the at least three different light-emitting units, a thickness of at least one buffer encapsulation layer corresponding to at least one light-emitting unit among the at least three different light-emitting units is different from respective thicknesses of the other buffer encapsulation layers corresponding to the other light-emitting units among the at least three different light-emitting units, one of the at least three different light-emitting units comprises an anode, a light-emitting layer, and a cathode layer, and as a viewing angle increases in a range, a rate at which a brightness of the light emitted from the third light-emitting unit decays is greater than a rate at which a brightness of the light emitted from the first light-emitting unit decays and a rate at which a brightness of the light emitted from the second light-emitting unit decays respectively, and a thickness of the cathode layer of the third light-emitting unit is less than a thickness of the cathode layer of the first light-emitting unit and a thickness of the cathode layer of the second light-emitting unit respectively.

13. The display panel of claim 1 , wherein a thickness of one of the at least three buffer encapsulation layers is in a range from 30 nm to 80 nm.

14. The display panel of claim 2 , wherein a thickness of one of the light extraction layers is in a range from 50 nm to 120 nm.

15. The display panel of claim 11 , wherein a thickness of the cathode layer of each of the first light-emitting unit, the second light-emitting unit, and the third light-emitting unit is in a range from 15 nm to 23 nm.

16. The display panel of claim 3 , wherein a color of light emitted from the first light-emitting unit is red, a color of light emitted from the second light-emitting unit is green, and a color of light emitted from the third light-emitting unit is blue.

17. A display device, comprising a display panel, wherein the display panel comprises:

a substrate;

at least three different light-emitting units disposed on the substrate and emitting at least three different colors; and

at least three buffer encapsulation layers disposed on a side of the at least three different light-emitting units facing away from the substrate, wherein the at least three buffer encapsulation layers are in one-to-one correspondence with the at least three different light-emitting units, a thickness of at least one buffer encapsulation layer corresponding to at least one light-emitting unit among the at least three different light-emitting units is different from respective thicknesses of the other buffer encapsulation layers corresponding to the other light-emitting units among the at least three different light-emitting units, and thicknesses of each cathode layer of the at least three different light-emitting units vary in proportion to rates at which brightness of light emitted from each light-emitting unit decays.

18. The A-display device of claim 17 , wherein the display device is used in a mobile phone, a wearable device with a display function, or a computer.

19. A display panel, comprising:

a substrate;

at least three different light-emitting units disposed on the substrate and configured to emit at least three different colors;

at least three buffer encapsulation layers disposed on a side of the at least three different light-emitting units facing away from the substrate, wherein the at least three buffer encapsulation layers are in one-to-one correspondence with the at least three different light-emitting units and one of the at least three different light-emitting units comprises an anode, a light-emitting layer, and a cathode layer, and the plurality of light extraction layers is in direct contact with the cathode layer; and

a plurality of light extraction layers disposed on one side of the at least three buffer encapsulation layers adjacent to the at least three different light-emitting units, wherein a thickness of at least one buffer encapsulation layer corresponding to at least one light-emitting unit among the at least three different light-emitting units is different from respective thicknesses of the other buffer encapsulation layers corresponding to the other light-emitting units among the at least three different light-emitting units.

20. The display panel of claim 19 , wherein a refractive index of the at least three buffer encapsulation layers is less than a refractive index of the plurality of light extraction layers, and the at least three buffer encapsulation layers are at a same layer.