The present invention relates to a an organic electroluminescent device comprising at least one light-emitting layer B comprising at least one host material H.sup.B, at least one thermally activated delayed fluorescence (TADF) material E.sup.B, and at least one small full width at half maximum (FWHM) emitter S.sup.B wherein E.sup.B transfers energy to S.sup.B and S.sup.B emits light with an emission maximum in the wavelength range from 500 nm to 560 nm.

This disclosure relates to the technical field of carbon nanotubes, provides an ultra-long chiral carbon nanotube and a method for preparing the same. The ultra-long chiral carbon nanotube has a diameter of about 1.5 nm to 5.5 nm and has a length of about 100 mm to 650 mm, the ultra-long chiral carbon nanotube includes a double-walled carbon nanotube and a triple-walled carbon nanotube, and each layer of the ultra-long chiral carbon nanotube is semiconducting and has a helix angle greater than 10°.

The present invention relates to organic electroluminescent devices, the emitting layer thereof containing a blend of a luminescent material having a narrow singlet-triplet gap and a fluorescent emission material having high steric shielding.

A display apparatus having high external light transmittance and a manufacturing method of the display apparatus are provided, wherein the display apparatus does not substantially include a common electrode in a transmission region. Particularly, a display apparatus includes a first substrate, a second substrate facing the first substrate, and a display unit interposed between the first substrate and the second substrate.

An organic electroluminescence device includes: an anode; an emitting layer; and a cathode, the emitting layer containing a first material, a second material and a third material, the first material being a fluorescent material, the second material being a delayed fluorescent material, the third material having a singlet energy larger than a singlet energy of the second material.

An embodiment of the present disclosure provides an organic light emitting diode comprising a first electrode; a second electrode facing the first electrode; and a first emitting material layer including a first delayed fluorescent dopant and a first phosphorescent dopant and disposed between the first and second electrodes, wherein a percentage by weight of the first phosphorescent dopant with respect to the first delayed fluorescent dopant is equal to or less than 5.

An organic light-emitting device having improved efficiency and lifespan includes: a first electrode, a second electrode, and an organic layer between the first electrode and the second electrode, wherein the organic layer includes an emission layer, the emission layer includes a first compound, a second compound, a third compound, and a fourth compound, the first compound, the second compound, the third compound, and the fourth compound are different from each other, the third compound includes a metal element having an atomic number of 40 or more, the fourth compound includes boron (B), the third compound and the fourth compound each satisfy Conditions 1-1 and 1-2 below, and the fourth compound satisfies Condition 2 or 3:

T.sub.1(C3).sub.onset≥S.sub.1(C4).sub.onset  Condition 1-1

T.sub.1(C3).sub.max≥S.sub.1(C4).sub.max  Condition 1-2

K.sub.RISC(C4)≥10.sup.3 S.sup.−1  Condition 2

f(C4)≥0.1.  Condition 3

A display substrate includes a backplane, first light-emitting devices capable of emitting first color light, second light-emitting devices capable of emitting second color light that are all disposed on the backplane, a low-refractive-index intercalation layer disposed at a side, away from the backplane, of the first light-emitting devices and the second light-emitting devices, and an encapsulation layer. The encapsulation layer includes a first inorganic barrier layer, a first organic barrier layer and a second inorganic barrier layer that are sequentially stacked on a side of the low-refractive-index intercalation layer away from the backplane. A refractive index of the low-refractive-index intercalation layer is less than a refractive index of the first inorganic barrier layer. In a direction perpendicular to the backplane, a transmittance of the low-refractive-index intercalation layer to the first color light is less than a transmittance of the low-refractive-index intercalation layer to the second color light.

A foldable electronic device module includes: a glass-containing cover element having a thickness from about (25) μm to about (200) μm, an elastic modulus from about (20) to (140) GPa, and first and second primary surfaces; a stack comprising: (a) an interlayer having an elastic modulus from about (0.01) to (10) GPa and a thickness from about 50 to (200) μm, and (b) a flexible substrate having a thickness from about (100) to (200) μm; and a first adhesive joining the stack to the cover element, and comprising an elastic modulus from about (0.001) to (10) GPa and a thickness from about (5) to (25) μm. Further, the module comprises an impact resistance characterized by tensile stresses of less than about (4100) MPa and less than about (8300) MPa at the first and second primary surfaces of the cover element, respectively, upon an impact in a Pen Drop Test.

A display panel includes a base substrate; and a light-emitting device layer, disposed on the base substrate and including sub-pixels. A sub-pixel includes light-emitting regions and a non-light-emitting regions located between adjacent light-emitting regions. The display panel includes a light-shielding layer, disposed on the side of the light-emitting device layer away from the base substrate and including a light-shielding structure located in the non-light-emitting region; and a polarizer, disposed on the side of the light-shielding layer away from the base substrate and having an absorption axis in a first direction. In each sub-pixel, along the first direction, the minimum distance between the boundary of the light-emitting region and the light-shielding structure is a first distance B; along a second direction intersected with the first direction, the minimum distance between the boundary of the light-emitting region and the light-shielding structure is a second distance A; and B>A.