US 12,464,885 B2
Light emitting device, display substrate and display equipment
Lei Chen, Beijing (CN); Xueqin Chen, Beijing (CN); and Yuqian Sun, Beijing (CN)
Assigned to Beijing BOE Technology Development Co., Ltd., Beijing (CN)
Filed by BOE Technology Group Co., Ltd., Beijing (CN)
Filed on Oct. 27, 2021, as Appl. No. 17/512,547.
Claims priority of application No. 202110308623.5 (CN), filed on Mar. 23, 2021.
Prior Publication US 2022/0320451 A1, Oct. 6, 2022
Int. Cl. H10K 50/18 (2023.01); H10K 50/11 (2023.01); H10K 50/13 (2023.01); H10K 50/15 (2023.01); H10K 50/16 (2023.01); H10K 50/17 (2023.01); H10K 101/40 (2023.01)
CPC H10K 50/11 (2023.02) [H10K 50/13 (2023.02); H10K 50/15 (2023.02); H10K 50/16 (2023.02); H10K 50/17 (2023.02); H10K 50/171 (2023.02); H10K 50/18 (2023.02); H10K 50/181 (2023.02); H10K 2101/40 (2023.02)] 20 Claims
OG exemplary drawing
 
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 5×1010 Ω/sq to 5×1011 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.