A display device includes a light-emitting-element layer including a plurality of light-emitting elements each including a first electrode, a functional layer, and a second electrode. The plurality of light-emitting elements are formed to emit lights in different colors. A nanoparticle layer is provided on a surface of the first electrode toward a light-emitting layer, and contains metal oxide nanoparticles that are electrically conductive.

A cadmium-free, core shell quantum dot, a quantum dot polymer composite, and electronic devices including the quantum dot polymer composite. The core shell quantum dot has an extinction coefficient per gram of greater than or equal to 0.3, an ultraviolet-visible absorption spectrum curve that has a positive differential coefficient value at 450 nm, wherein the core shell quantum dot includes a semiconductor nanocrystal core including indium and phosphorus, and optionally zinc, and a semiconductor nanocrystal shell disposed on the semiconductor nanocrystal core, the shell including zinc, selenium, and sulfur, wherein the core shell quantum dot has a quantum efficiency of greater than or equal to about 80%, and is configured to emit green light upon excitation.

A light-emitting element includes a light-emitting layer, and the light-emitting layer includes a plurality of quantum dots covered by shells containing a ferritin protein.

A light-emitting element is provided with an interlayer organic layer having electron transport properties. At a HOMO level, an energy level difference between a first hole transport layer and the second hole transport layer is from 0.0 eV to 0.20 eV, and at a LUMO level, an energy level difference between a first electron transport layer and a second electron transport layer, and an energy level difference between the first electron transport layer and the blue light-emitting layer are each from 0.0 eV to 0.20 eV. Alternatively, the light-emitting element is provided with the interlayer organic layer between the electron transport layer and the cathode electrode, the electron transport layer is formed from a lithium quinolate complex and an organic compound having electron transport properties, and the interlayer organic layer is formed from an organic compound including an amino group or a hydroxyl group.

A light-emitting device, includes: a substrate transparent to light a first light-emitting layer provided above the substrate and containing first quantum dots configured to emit a first light a second light-emitting layer provided above the substrate and configured to emit a second light shorter in wavelength than the first light a pair of first color-correcting layers each correspondingly provided to one of above or below the first light-emitting layer to overlap with at least a portion of the first light-emitting layer in plan view, transmitting the first light, and absorbing light shorter in wavelength than the first light and a pair of second color-correcting layers each correspondingly provided to one of above or below the second light-emitting layer to overlap with the second light-emitting layer in plan view, transmitting the second light, and absorbing light longer in wavelength than the second light.

An organic light emitting diode comprises a hole transport layer, an emissive layer, and an electron transport layer. The hole transport layer and optionally the electron transport layer is made of a material having a refractive index having a specific anisotropy.

An organic light emitting diode comprises a hole transport layer, an emissive layer, and an electron transport layer. The hole transport layer and optionally the electron transport layer is made of a material having a refractive index having a specific anisotropy.

A deposition mask includes: a first surface and a second surface, in which a plurality of through-holes are formed; a pair of long side surfaces connected to the first and second surfaces, and defining a profile of the deposition mask in a longitudinal direction of the deposition mask; and a pair of short side surfaces connected to the first and second surfaces, and defining a profile of the deposition mask in a width direction of the deposition mask. The long side surface includes a first portion that is recessed inside and includes a first end portion positioned along the first surface, and a second end portion positioned along the second surface and positioned inside the first end portion. The through-hole includes a first recess formed on the first surface, and a second recess formed on the second surface and connected to the first recess through a hole connection portion.

The invention provides a display device in which the tint is difficult to observe in a case where white display is visually confirmed from a front direction, and the tint is also difficult to observe at any azimuthal angle in a case where white display is visually confirmed from an oblique direction. A display device of the invention includes, from a viewing side, an anisotropic light absorbing layer and a self light emitting display element which emits at least red light, green light, and blue light, the self light emitting display element has a microcavity structure, the anisotropic light absorbing layer is formed of a composition containing a dichroic substance and a liquid crystal compound, the dichroic substance has a maximum absorption wavelength of 400 to 500 nm, and the anisotropic light absorbing layer satisfies a requirement represented by Expression (1) and a requirement represented by Expression (2),

1.50<Amax(60)/A(0)  Expression (1)

1.00≤Amax(60)/Amin(60)≤1.20.  Expression (2)

The present invention relates to preparation and application of a novel quadridentate platinum (II) complex, and belongs to the field of OLED organic electroluminescent materials. The complex of the present invention has NCNC chelating coordination, a stable structure, a spiro ring structure in the skeleton, a strong molecular stereoscopic property, and weak intermolecular interaction, so that mutual stacking between complex molecules is avoided, the formation of an excimer is greatly inhibited, and thus the efficiency of an OLED device is improved. The complex of the present invention has high fluorescence quantum efficiency, great thermal stability and low quenching constant, and can be used for manufacturing a red-light OLED device with high luminescence efficiency and low roll-off.

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