Light emitting device, display substrate and display equipment

1 . A light emitting device, comprising a hole injection layer, a hole transport layer, an electron blocking layer, a light emitting layer and an electron injection layer that are stacked in sequence,

wherein the light emitting layer comprises a plurality of light emitting units, and wavelengths of lights emitted by at least two of the plurality of light emitting units are different from each other;

wherein a hole mobility of the electron blocking layer is greater than or equal to a hole mobility of the hole injection layer or the hole transport layer;

wherein a square resistance of the hole injection layer and a square resistance of the hole transport layer are both in a range from 5×10 10 Ω/sq to 5×10 11 Ω/sq,

wherein the plurality of light emitting units comprises a first light emitting unit and a second light emitting unit, and a wavelength of the light emitted by the first light emitting unit is less than a wavelength of the light emitted by the second light emitting unit;

wherein the hole mobility of the hole injection layer is equal to the hole mobility of the hole transport layer and is the first hole mobility, a hole mobility of a region of the electron blocking layer corresponding to the first light emitting unit is a second hole mobility, a hole mobility of a region of the electron blocking layer corresponding to the second light emitting unit is a third hole mobility, a ratio of the second hole mobility to the first hole mobility is a first ratio, a ratio of the third hole mobility to the first hole mobility is a second ratio, and the first ratio is greater than the second ratio,

wherein the plurality of light emitting units further comprises a third light emitting unit, and the wavelength of the light emitted by the second light emitting unit is less than a wavelength of the light emitted by the third light emitting unit; and

wherein a hole mobility of a region of the electron blocking layer corresponding to the third light emitting unit is a fourth hole mobility, a ratio of the fourth hole mobility to the first hole mobility is a third ratio, and the second ratio is greater than the third ratio.

2 . The light emitting device of claim 1 , wherein the square resistance of the hole injection layer and the square resistance of the hole transport layer are both in a range from 5×10 10 Ω/sq to 2×10 11 Ω/sq.

3 . The light emitting device of claim 1 , wherein the first ratio is greater than 1 and less than or equal to 100, and the second ratio is greater than 1 and less than or equal to 11.

4 . The light emitting device of claim 3 , wherein the first ratio is in a range from 50 to 100, and the second ratio is in range from great than 2 to 10.

5 . The light emitting device of claim 1 , wherein the first ratio is greater than 1 and less than or equal to 100, the second ratio is greater than 1 and less than or equal to 11, and the third ratio is in a range from 1 to 10.

6 . The light emitting device of claim 5 , wherein the first ratio is in a range from greater than 50 to 100, the second ratio is in a range from 2 to 10, and the third ratio is in a range from 2 to 8.

7 . The light emitting device of claim 1 , wherein the first light emitting unit has a blue light emitting material, the second light emitting unit has a green light emitting material, and the third light emitting unit has a red light emitting material.

8 . The light emitting device of claim 1 , wherein the hole mobility of the hole injection layer and the hole mobility of the hole transport layer are both in a range from 5×10 −4 cm 2 /Vs to 5×10 −5 cm 2 /Vs.

9 . The light emitting device of claim 1 , further comprising an electron transport layer located between the light emitting layer and the electron injection layer.

10 . The light emitting device of claim 9 , further comprising a hole blocking layer located between the light emitting layer and the electron transport layer.

11 . A display substrate, comprising the light emitting device of claim 1 .

12 . The display substrate of claim 11 , wherein the first ratio is greater than 1 and less than or equal to 100, and the second ratio is greater than 1 and less than or equal to 11.

13 . The display substrate of claim 12 , wherein the first ratio is in a range from 50 to 100, and the second ratio is in range from great than 2 to 10.

14 . The display substrate of claim 11 , wherein the first ratio is greater than 1 and less than or equal to 100, the second ratio is greater than 1 and less than or equal to 11, and the third ratio is in a range from 1 to 10.

15 . The display substrate of claim 14 , wherein the first ratio is in a range from greater than 50 to 100, the second ratio is in a range from 2 to 10, and the third ratio is in a range from 2 to 8.

16 . A display equipment, comprising the display substrate of claim 11 .

17 . The display substrate of claim 11 , wherein the first light emitting unit has a blue light emitting material, the second light emitting unit has a green light emitting material, and the third light emitting unit has a red light emitting material.

18 . The display substrate of claim 11 , wherein the hole mobility of the hole injection layer and the hole mobility of the hole transport layer are both in a range from 5×10 −4 cm 2 /Vs to 5×10 −5 cm 2 /Vs.

19 . The display substrate of claim 11 , further comprising an electron transport layer located between the light emitting layer and the electron injection layer.

20 . The display substrate of claim 19 , further comprising a hole blocking layer located between the light emitting layer and the electron transport layer.