Array substrate, display panel and display device

1. An array substrate, comprising: a base substrate, electroluminescent devices located on the base substrate, and a reflection structure located on a side away from light exiting surfaces of the electroluminescent devices,

wherein the reflection structure comprises at least two groups of Bragg reflectors configured to reflect visible light in preset wave bands, and the preset wave bands reflected by different groups of Bragg reflectors are different, and the preset wave bands do not completely overlap; and

wavelength ranges of light emitted by the electroluminescent devices overlap with wavelength ranges of light reflected by the at least two groups of Bragg reflectors corresponding to the electroluminescent devices;

wherein the electroluminescent devices respectively comprise an anode layer, a cathode layer, and a luminescent layer located between the anode layer and the cathode layer;

wherein the at least two groups of Bragg reflectors comprise indium tin oxide functional layers with different oxygen concentrations; and

the at least two groups of Bragg reflectors are reused as the cathode layer or the anode layer of the electroluminescent devices.

2. The array substrate according to claim 1 , wherein each of the at least two groups of Bragg reflectors comprises at least two pairs of stacked functional layers, and each pair of the at least two pairs of stacked functional layers comprise a plurality of first functional layers and a plurality of second functional layers, the plurality of first functional layers and the plurality of second functional layers are stacked and have different refractive indexes; and

the plurality of first functional layers and the plurality of second functional layers are alternately arranged, and the plurality of first functional layers have a same refractive index and a same thickness, and the plurality of second functional layers have a same refractive index and a same thickness.

3. The array substrate according to claim 2 , wherein in each pair of the at least two pairs of stacked functional layers, a refractive index of a first functional layer is less than or equal to 1.5, and a refractive index of a second functional layer is greater than or equal to 2.5.

4. The array substrate according to claim 2 , wherein in each pair of the at least two pairs of stacked functional layers, the first functional layer and the second functional layer are same in thickness, and a thickness of one pair of functional layers is calculated through following formulas:

Δ

⁢

⁢

f

0

f

0

=

4

π

⁢

arcsin

⁡

(

n

2

-

n

1

n

2

+

n

1

)

d

=

1

4

⁢

f

0

where Δf 0 represents a frequency bandwidth of a photonic band gap; f 0 represents a wave band corresponding to a center frequency band of the photonic band gap; n 1 represents the refractive index of the first functional layer; n 2 represents the refractive index of the second functional layer; and d represents the thicknesses of one pair of functional layers.

5. The array substrate according to claim 2 , wherein each group of Bragg reflector comprises 2-20 pairs of functional layers.

6. The array substrate according to claim 2 , wherein in each pair of the at least two pairs of stacked functional layers, the first functional layer comprises silicon dioxide, and the second functional layer comprises titanium dioxide;

or, in each pair of the at least two pairs of stacked functional layers, the first functional layer is a first indium tin oxide layer, the second functional layer is a second indium tin oxide layer, and an oxygen content of the first indium tin oxide layer is different from an oxygen content of the second indium tin oxide layer.

7. The array substrate according to claim 1 , wherein the at least two groups of Bragg reflectors are stacked.

8. The array substrate according to claim 1 , wherein the electroluminescent devices comprise a red electroluminescent device, a green electroluminescent device, and a blue electroluminescent device.

9. The array substrate according to claim 8 , comprising two groups of Bragg reflectors, wherein a first group of Bragg reflector is configured to reflect visible light in a wave band of 580-750 nm, and a second group of Bragg reflector is configured to reflect visible light in a wave band of 405-595 nm.

10. The array substrate according to claim 8 , comprising three groups of Bragg reflectors, wherein a first group of Bragg reflector is configured to reflect visible light in a wave band of 620-750 nm, a second group of Bragg reflector is configured to reflect visible light in a wave band of 495-595 nm, and a third group of Bragg reflector is configured to reflect visible light in a wave band of 405-475 nm.

11. The array substrate according to claim 1 , wherein a material of the cathode layer and a material of the anode layer are transparent conductive oxides.

12. The array substrate according to claim 1 , wherein the luminescent layer comprise a quantum dot luminescent material.

13. A display panel, comprising the array substrate according to claim 1 .

14. A display device, comprising the display panel according to claim 13 .

15. A manufacturing method of the array substrate according to claim 1 , comprising steps of:

providing a base substrate;

forming electroluminescent devices on the base substrate;

forming a reflection structure on a side away from light exiting surfaces of the electroluminescent devices,

wherein the reflection structure comprises at least two groups of Bragg reflectors configured to reflect visible light in preset wave bands, the preset wave bands reflected by different groups of Bragg reflectors are different, the preset wave bands do not completely overlap, and wavelength ranges of light emitted by the electroluminescent devices overlap with wavelength ranges of light reflected by the at least two groups of Bragg reflectors corresponding to the electroluminescent devices.

16. The manufacturing method of the array substrate according to claim 15 , wherein when stacked functional layers in the at least two groups of Bragg reflectors are made from indium tin oxide materials, the step of forming the reflection structure on the side away from the light exiting surfaces of the electroluminescent devices comprises:

sputtering indium tin oxide at an atmosphere having an oxygen concentration of 5% by magnetron sputtering to form a first functional layer;

sputtering indium tin oxide at an atmosphere having an oxygen concentration of 15% by magnetron sputtering to form a second functional layer; and

alternately performing above steps until the manufacturing of the reflection structure is completed.