A light-emitting element with high emission efficiency. The light-emitting element includes a first organic compound, a second organic compound, and a guest material. The LUMO level of the first organic compound is lower than the LUMO level of the second organic compound. The HOMO level of the first organic compound is lower than the HOMO level of the second organic compound. The HOMO level of the guest material is higher than the HOMO level of the second organic compound. The energy difference between the LUMO level of the guest material and the HOMO level of the guest material is larger than the energy difference between the LUMO level of the first organic compound and the HOMO level of the second organic compound. The guest material has a function of converting triplet excitation energy into light emission. The first organic compound and the second organic compound form an exciplex.

A light emitting device including a first electrode, a light emitting portion on the first electrode, the light emitting portion including a plurality of light emitting units and at least one interconnecting layer between ones of the light emitting units that are adjacent to each other, and a second electrode on the light emitting portion. The at least one interconnecting layer includes a p-type charge generation layer doped with a p-type dopant and an n-type charge generation layer doped with an n-type dopant. At least one of the p-type charge generation layer and the n-type charge generation layer has a concentration gradient of the p-type dopant or the n-type dopant.

The present invention relates to an OLED internal light extraction scheme with graded-index layer and embedded scattering particles.

To provide a display device including a light emitting element layer including an anode electrode, a light emissive layer formed on the anode electrode, and a cathode electrode formed on the light emissive layer, and a bank formed on the lower electrode and having an opening, in which the lower electrode is partially exposed, wherein the light emissive layer includes a p-doped hole transport layer containing p-dopant, and the p-doped hole transport layer contains a larger amount of p-dopant in an area close to an end portion of the opening of the bank than the amount of p-dopant contained in other areas.

The disclosure provides an organic electroluminescent display device, including a substrate, an organic electroluminescent device disposed on the substrate, and a thin film packaging structure disposed on the substrate and packaging the organic electroluminescent device. The thin film packaging structure has desiccant particles. The disclosure further provides a manufacturing method of the organic electroluminescent display device, which can reduce the influence of vapor attached on surfaces of multiple layers of packaging thin films or infiltrated in the multiple layers of packaging thin films on the packaged organic electroluminescent device, so as to prolong the service life of the organic electroluminescent device.

The present application discloses a first aspect provides a quantum dot light-emitting diode, including: a cathode and an anode which are oppositely arranged; a quantum dot light-emitting layer arranged between the cathode and the anode; and a stacked layer arranged between the cathode and the quantum dot light-emitting layer. A stacked layer includes: a first metal oxide nanoparticle layer, and a mixed material layer arranged on a surface of the first metal oxide nanoparticle layer far away from the quantum dot light-emitting layer. The mixed material layer includes: first metal oxide nanoparticles, and a second metal oxide dispersed among gaps of the first metal oxide nanoparticles. First metal oxide nanoparticles in the first metal oxide nanoparticle layer serve as an electron transport material. A content of the second metal oxide in the mixed material layer gradually increases in a direction from the quantum dot light-emitting layer to the cathode.

A novel light-emitting device, a light-emitting device with high emission efficiency, a light-emitting device with a long lifetime, or a light-emitting device with low driving voltage is provided. An EL layer includes a first layer, a second layer, a third layer, a light-emitting layer, and a fourth layer in this order from the anode side. The first layer contains a first organic compound and a second organic compound. The fourth layer contains a seventh organic compound. The first organic compound exhibits an electron-accepting property with respect to the second organic compound. A HOMO level of the second organic compound is higher than or equal to ?5.7 eV and lower than or equal to ?5.4 eV. The fourth layer includes a region where the amount of seventh organic compound is large and a region where the amount of seventh organic compound is small in the thickness direction.

Provided are an organic/inorganic/hybrid perovskite nanocrystal particle light-emitter having a gradient structure, a method of producing the same, and a light emitting element using the same. The organic/inorganic/hybrid perovskite nanocrystal particle light-emitter having a gradient structure includes an organic/inorganic/hybrid perovskite nanocrystal which is dispersible in an organic solvent, wherein the nanocrystal has a gradient composition in which a composition is changed from the center thereof to the outside. Therefore, the gradual change in the content in the nanocrystal may be used to uniformly adjust a fraction in the nanocrystal, to reduce surface oxidation, and to improve exciton confinement in the perovskite present in large quantities inside the nanocrystal, and thus light luminescence efficiency may be improved and durability and stability may be increased.

An organic light-emitting device, including: an anode and a cathode opposite each other, a first stack and a second stack between the anode and the cathode, and a charge generation layer between the first stack and the second stack, the charge generation layer including an n-type charge generation layer and a p-type charge generation layer, wherein the p-type charge generation layer includes one first organic material, wherein the n-type charge generation layer includes a second organic material and an n-type dopant, wherein the n-type charge generation layer is divided into a first region contacting the first stack, a second region contacting the p-type charge generation layer, and a third region between the first region and the second region, and wherein a dopant content of the n-type dopant is stepwise increased in an order of: the first region, the third region, and the second region.

An organic light emitting device includes an anode, the anode including a conductive polymer, a fluorine-containing organic material, and metal nanoparticles, a cathode facing the anode, and an emission layer between the anode and the cathode.