A light-emitting device including a first electrode, a second electrode facing the first electrode, and an interlayer arranged between the first electrode and the second electrode and including an emission layer is provided. The emission layer includes a first emission layer and a second emission layer. The first emission layer includes a phosphorescent emitter and a first host. The second emission layer includes a fluorescent emitter and a second host. The phosphorescent emitter is configured to emit a first light having a first emission spectrum, and the first light is blue light.

Provided is an organic electroluminescent device. The organic electroluminescent device is a bottom-emitting single-layer device. The device has maximum external quantum efficiency EQE.sub.max of more than 26%, and has a high roll-off coefficient of greater than or equal to 0.91 at high brightness of 5000 cd/m.sup.2 or 11500 cd/m.sup.2.

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.

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.

The present invention relates to organic electroluminescent devices including one or more light-emitting layers B, 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 excitation energy transfer components EET-2, and 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.

An organic electroluminescent device and a display apparatus, where the organic electroluminescent device includes an anode functional layer, a first electron blocking layer, a second electron blocking layer, a light-emitting layer and a cathode functional layer; the first electron blocking layer includes a red light electron blocking layer and a green light electron blocking layer, which are disposed side by side, and the second electron blocking layer is a blue light electron blocking layer; a HOMO energy level of a red light electron blocking material in the red light electron blocking layer and a HOMO energy level of a green light electron blocking material in the green light electron blocking layer are both lower than a HOMO energy level of a blue light electron blocking material in the blue light electron blocking layer.