An electroluminescent element according to an aspect of the disclosure includes: a pair of a cathode electrode and an anode electrode; a light-emitting layer provided between the cathode electrode and the anode electrode; an electron transport layer provided between the cathode electrode and the light-emitting layer; and a hole transport layer provided between the anode electrode and the light-emitting layer. The light-emitting layer includes ZnSe-based quantum dots including ZnSe and one of the electron transport layer and the hole transport layer is composed of ZnO particles having an average particle size of 3 nm or greater and 30 nm or less.

An electronic device for skin management or skin treatments including an active area including a light emission area and a non-light emission area comprises a plurality of organic light emitting devices disposed in the light emission area and emitting same color light; and first to third wavelength converting layers overlapping the light emission area and a part of the non-light emission area, wherein light emitted from the plurality of organic light emitting devices is extracted to outside the electronic device through the first to third wavelength converting layers.

A flexible display panel includes a flexible substrate including a first region including a display region and having a curved display surface, and a plurality of non-display regions that is located outside the display region and including a second region located outside the first region and folded in a direction different from a display direction of the first region, and an encapsulation member for encapsulating the display region along the curved display surface.

A display substrate includes a substrate (10) that is divided into a plurality of subpixel areas, a drive transistor (20) and a photodetector (30) in each of the plurality of subpixel areas, and an insulation layer (40) on the photodetector (30). The drive transistor (20) includes an electrode layer that includes a source electrode (21) and a drain electrode (22). The photodetector (30) is coupled to one of the source electrode (21) and the drain electrode (22). An entirety of an orthographic projection of the insulation layer (40) on the substrate is inside an orthographic projection of the electrode layer on the substrate (10).

A luminous body includes a first moiety including a plurality of first ligands combined to a surface of an inorganic emitting particle; and a second moiety including silsesquioxanes connected to a second ligand connected to one of the first ligands, wherein one of the first and second ligands is a polar ligand, and the other one of the first and second ligands is a non-polar ligand.

A light extraction apparatus for an organic light-emitting diode (OLED) includes an OLED emitter (100), a plurality of tapered reflectors (210), and a spacer layer (202). Each tapered reflector includes a first surface (212), a second surface (214) opposite to the first surface and comprising a surface area larger than a surface area of the first surface, and at least one side surface (216) extending between the first surface and the second surface. The spacer layer (202) includes a first surface coupled to the OLED emitter and a second surface coupled to the first surface of each of the plurality of tapered reflectors. Light emitted from the OLED passes through the spacer layer and into the plurality of tapered reflectors. The at least one side surface of each of the plurality of tapered reflectors includes a slope to redirect light into an escape cone and out of the second surface of the corresponding tapered reflector.

An electroluminescent element according to an aspect of the disclosure includes: a pair of a cathode electrode and an anode electrode; a light-emitting layer provided between the cathode electrode and the anode electrode; an electron transport layer provided between the cathode electrode and the light-emitting layer; and a hole transport layer provided between the anode electrode and the light-emitting layer. The light-emitting layer includes ZnSe-based quantum dots including ZnSe and one of the electron transport layer and the hole transport layer is composed of ZnO particles having an average particle size of 3 nm or greater and 30 nm or less.

An organic-EL device includes an emitting-layer, first-layer adjacent to the emitting-layer near the anode, and second-layer adjacent to the emitting-layer near the cathode. The emitting-layer contains first, second and third compounds. The first-layer contains a compound of formula-(A). The second-layer contains a compound of formula-(B). The first, second and third compounds are a fluorescent compound of formula-(1), delayed-fluorescent compound of formula-(2), and compound of formula-(3), respectively. Singlet energies S.sub.1 of the first to third compounds satisfy S.sub.1(M3)>S.sub.1(M2)>S.sub.1(M1). In the formula-(A), Ra.sub.1-Ra.sub.5 etc. each represent a substituent etc. In the formula-(B), X.sub.1-X.sub.3 each represent N atom etc, Ar.sub.1 and Ar.sub.2 each represent a group of formula-(1B) etc. A represents the group of the formula-(1B). In the formula-(1B), HAr is of formula-(2B), a is 1 to 5, and L.sub.1 is a linking group etc. In the formula-(2B), X.sub.11-X.sub.18 each represent N atom etc, and Y.sub.1 represent O, S, or N atom etc.

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A light emitting photonic crystal having an organic light emitting diode and methods of making the same are disclosed. An organic light emitting diode disposed within a photonic structure having a band-gap, or stop-band, allows the photonic structure to emit light at wavelengths occurring at the edges of the band-gap. Photonic crystal structures that provide this function may include materials having a refractive index that varies.

An organic light emitting device and a method of manufacturing an organic light emitting device. The organic light emitting device includes a transparent light extracting component including a light outputting layer on a light outputting side, and at least one surface of the light outputting layer has a first wavy shape.