A light-emitting element includes: an electron transport layer; a hole transport layer; and a light-emitting layer between the electron transport layer and the hole transport layer, the light-emitting layer including: quantum dots; and ligands coordinated to the quantum dots, wherein the ligands in the light-emitting layer have a lower concentration on an electron transport layer side of the light-emitting layer than on a hole transport layer side of the light-emitting layer.

A light-emitting diode (LED) structure includes a light-emitting diode including an emissive electroluminescent layer situated between two electrodes, a light extraction layer (LEL) comprising a UV-cured ink, and a UV blocking layer between the LEL and the light-emitting diode. The UV blocking layer has a thickness of 50-500 nm and at least 90% absorption to UV light of wavelengths for curing the UV-cured ink.

A display panel includes a display substrate, an opposite substrate, and a hydrophobic bonding portion disposed between the display substrate and the opposite substrate. The hydrophobic bonding portion is configured to bond the display substrate and the opposite substrate together, and an orthographic projection of the hydrophobic bonding portion on the display substrate is located outside a display region of the display substrate.

A display panel includes: a plurality of light emitting units each having a light emitting side and a back side; a transparent substrate disposed over the light emitting side of the light emitting unit; a transparent film disposed over a side of the transparent substrate opposing the light emitting unit, wherein: the transparent film has an effective refractive index smaller than a refractive index of the transparent substrate; and the transparent film has a position-dependent refractive index progressively smaller along a light emitting direction from the light emitting unit.

A light-emitting diode display including a substrate having a driving circuitry and a plurality of light emitting diode structures disposed on the substrate. Each light-emitting diode structure has a light emitting diode with a light emission zone having a planar portion, and a pigmentless light extraction layer of a UV-cured ink disposed over the light-emitting diode. The light extraction layer has a gradient in index of refraction along an axis normal to the planar portion, and the index of refraction of the light extraction layer decreases with distance from the planar portion.

A display device is provided. The display device comprises a thin-film transistor layer disposed on a substrate, a light emitting element layer disposed on the thin-film transistor layer, a touch sensing layer disposed on the light emitting layer, and a reflection control layer disposed on the touch sensing layer, wherein the reflection control layer includes a UV absorber, wherein the UV absorber includes at least one hydrophobic group, and/or the UV absorber is present as a concentration gradient in the reflection control layer.

An organic light-emitting diode (OLED) structure includes a stack of OLED layers; a light extraction layer (LEL) comprising a UV-cured ink; and a UV blocking layer between the LEL and the stack of OLED layers.

The first region (RG1) contains a first organic material and a metal compound (a compound containing a metal element). The second region (RG2) contains the first organic material and the metal compound. The average intensity of the SIMS profile of the metal element in the second region (RG2) can be lower than the average intensity of the SIMS profile of the metal element in the first region (RG1). Specifically, the average intensity of the SIMS profile of the metal element in the second region (RG2) can be lower than 10%, preferably lower than 1.0%, of the average intensity of the SIMS profile of the metal element in the first region (RG1).

A technique is provided that improves the efficiency of electron and hole injection in a light-emitting element containing quantum dots in a light-emitting layer thereof and hence improves the luminous efficiency thereof The light-emitting element includes on a substrate: a positive electrode; a negative electrode; a quantum-dot layer between the positive electrode and the negative electrode, the quantum-dot layer including a stack of a plurality of luminous, first quantum dots and a plurality of non-luminous, second quantum dots; a hole transport layer between the positive electrode and the quantum-dot layer; and an electron transport layer between the negative electrode and the quantum-dot layer, the plurality of second quantum dots being more numerous in an electron transport layer side than in a hole transport layer side.

A display device according to an embodiment of the present invention includes: a substrate; a lower electrode provided above the substrate; an insulating film provided above the lower electrode and having an opening; an organic layer arranged at least partly in the opening and electrically connected to the lower electrode; and an upper electrode electrically connected above the organic layer; the organic layer includes a hole injection layer, the opening includes a first area arranged to a center side, and a second area arranged on an outer side of the first area, and the hole injection layer has a higher p-dopant concentration in the first area than in the second area.