A light-emitting device that emits green light includes a first electrode and a second electrode that are arranged in sequence, and a light-emitting layer disposed between the first electrode and the second electrode, the light-emitting layer includes a first host material and a second host material; the first host material and the second host material form an exciplex, a difference between a lowest unoccupied molecular orbital (LUMO) energy level of the first host material and a LUMO energy level of the second host material is greater than or equal to 0.5 eV, under a same test condition, a difference between an order of magnitude of a hole mobility of the first host material and an order of magnitude of an electron mobility of the second host material is greater than or equal to 1.

Embodiments provide a light emitting element that includes a first electrode, a second electrode disposed on the first electrode, and an emission layer disposed between the first electrode and the second electrode. The emission layer includes a polycyclic compound represented by Formula 1, which includes a boron-containing core moiety, and a spiro-bifluorene substituent, thereby exhibiting high efficiency and long service life characteristics:

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The present invention relates to organic electroluminescent devices including one or more light-emitting layers, each of which is composed of one or more sublayers including as a whole one or more excitation energy transfer components EET-1, one or more hole scavengers H.sub.scav, one or more small full width at half maximum (FWHM) emitters S.sup.B emitting light with an FWHM of less than or equal to 0.25 eV. Furthermore, the present invention relates to a method for generating light by means of an organic electroluminescent device according to the present invention.

The present invention relates to organic electroluminescent devices including a light-emitting layers B including a TADF material, a small full width at half maximum (FWHM) emitter S.sup.B emitting blue light with an FWHM of less than or equal to 0.25 eV, and a host material H.sup.B, and an optional excitation energy transfer component EET-2. Furthermore, the present invention relates to a method for generating blue light by means of an organic electroluminescent device according to the present invention.

The present invention relates to a an organic electroluminescent device including at least one light-emitting layer B composed of one or more sublayers, wherein the one or more sublayers of the light-emitting layer B as a whole include at least one host material H.sup.B, at least one phosphorescence material P.sup.B, at least one small FWHM emitter S.sup.B, and optionally at least one TADF material E.sup.B, wherein S.sup.B emits light with a full width at half maximum (FWHM) of less than or equal to 0.25 eV.

An organic light-emitting device including a first electrode; a second electrode facing the first electrode; an interlayer arranged between the first electrode and the second electrode, wherein the interlayer comprises an emission layer; a first compound represented by Formula 1; and a second compound represented by Formula 2:

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wherein ring CY.sub.11 to ring CY.sub.14, ring CY.sub.23, and ring CY.sub.24 are each independently a C.sub.5-C.sub.30 carbocyclic group or a C.sub.1-C.sub.30 heterocyclic group; E.sub.1 is a group represented by Formula 1A; k1 is an integer from 1 to 5; n11 is an integer from 1 to 3; n12 is an integer from 0 to 3; X.sub.21 is N or C(R.sub.21a), X.sub.22 is N or C(R.sub.22a), X.sub.23 is N or C(R.sub.23a), and at least one of X.sub.21 to X.sub.23 is N; and the remaining substituents are as defined herein.

There are provided a composition, a light-emitting device including the composition, and an electronic apparatus including the light-emitting device, wherein the composition includes a first compound including at least one pyrrole-containing condensed cyclic group and a silicon-containing group, and not including an electron-transporting moiety, and a second compound including an azine group including at least one nitrogen, and not including a silicon-containing group.

The present invention relates to a an organic electroluminescent device including at least one light-emitting layer B composed of one or more sublayers, wherein the one or more sublayers of the light-emitting layer B as a whole include at least one host material H.sup.B, at least one phosphorescence material P.sup.B, at least one small FWHM emitter S.sup.B, and optionally at least one TADF material E.sup.B, wherein S.sup.B emits light with a full width at half maximum (FWHM) of less than or equal to 0.25 eV.

The present invention relates to an organic electroluminescent device including at least one light-emitting layer B composed of one or more sublayers, wherein the one or more sublayers of the light-emitting layer B including at least one host material H.sup.B, at least one phosphorescence material P.sup.B, at least one small FWHM emitter S.sup.B, and optionally at least one TADF material E.sup.B, wherein S.sup.B being to emit light with a full width at half maximum (FWHM) of less than or equal to 0.25 eV.

The invention relates to a an organic electroluminescent device including at least one light-emitting layer B composed of one or more sublayers, wherein the one or more sublayers of the light-emitting layer B as a whole include at least one host material H.sup.B, at least one phosphorescence material P.sup.B, at least one small FWHM emitter S.sup.B, and optionally at least one TADF material E.sup.B, wherein S.sup.B emits light with a full width at half maximum (FWHM) of less than or equal to 0.25 eV.