The present invention includes a novel series of host materials for OLEDs based on substituted fused 1,2,4-triazines. The compounds of the invention may improve the device EQE and lifetime.

A novel compound is disclosed which includes a ligand L.sub.A of Formula II,

##STR00001##

wherein: ring B is independently a 5-membered or 6-membered carbocyclic or heterocyclic ring; X.sup.1 to X.sup.4 are each independently selected from the group consisting of C, N, and CR; at least one pair of adjacent X.sup.1 to X.sup.4 are each C and fused to Formula V

##STR00002##  where indicated by “”; X.sup.5 to X.sup.12 are each independently C or N; the maximum number of N within a ring is two; Z and Y are each independently selected from the group consisting of O, S, Se, NR′, CR′R″, SiR′R″, and GeR′R″; R.sup.B and R.sup.C each independently represents zero, mono, or up to a maximum allowed substitutions to its associated ring; each of R.sup.B, R.sup.C, R, R′, and R″ is independently hydrogen or a substituent selected from the group consisting of deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carboxylic acid, ether, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, boryl, and combinations thereof; and two substituents can be joined or fused to form a ring; the ligand L.sub.A is complexed to a metal M through the two indicated dash lines of each Formula; and the ligand L.sub.A can be joined with other ligands to form a tridentate, tetradentate, pentadentate, or hexadentate ligand.

Provided is an organic electroluminescent device. The organic electroluminescent device comprises an anode, a cathode and an organic layer disposed between the anode and the cathode, wherein the organic layer comprises a first organic layer, the first organic layer contains a first organic material and a second organic material that satisfy particular energy level requirements, and the first organic layer has a conductivity greater than or equal to 3×10.sup.−5 S/m. The novel organic electroluminescent device effectively controls a hole injection ability so that the overall performance of the device is effectively improved. Further provided are an organic electroluminescent device and a first organic electroluminescent device.

A light-emitting device includes a first sub-pixel provided with a first light emitter, and a second sub-pixel provided with a second light emitter and constituting, together with the first sub-pixel, one of a plurality of pixels. The first light emitter has a first cathode, a first anode, and a first light-emitting layer containing a first quantum dot and disposed between the first cathode and the first anode. The second light emitter has a second cathode, a second anode, and a second light-emitting layer containing a second quantum dot and disposed between the second cathode and the second anode. The second quantum dot emits light having a longer light-emission wavelength than the first quantum dot. The first light-emitting layer is thicker than the second light-emitting layer.

The present disclosure provides an organic electroluminescent device including: an anode; a cathode; and one or more organic material layers interposed between the anode and cathode and selected from the group consisting of a hole injection layer, a hole transporting layer, a light emitting layer, an electron transporting layer, and an electron injection layer, and further including a lifetime enhancement layer (LEL) between the light emitting layer and the electron transporting layer.

The present disclosure provides an organic light-emitting diode and a display panel, the organic light-emitting diode including: a first electrode, a second electrode, a light-emitting layer, a hole blocking layer and an electron transport layer; the first electrode and the second electrode are oppositely arranged; the light-emitting layer is between the first electrode and the second electrode; the hole blocking layer is between the light-emitting layer and the second electrode; the electron transport layer is between the hole transport layer and the second electrode, wherein the energy level difference between the HOMO energy level of the hole blocking layer and the HOMO energy level of the light-emitting layer is larger than or equal to 0.1 eV, and the energy level difference between the HOMO energy level of the electron transport layer and the HOMO energy level of the hole blocking layer is larger than or equal to 0.1 eV.

A compound including a first bidentate ligand L.sub.A that includes a structure of Formula I,

##STR00001##

are provided. The ligand L.sub.A is coordinated to a metal M and can be joined with other ligands. In Formula I, in addition to some exclusions, each of X.sup.1, X.sup.2, X.sup.3, and X.sup.4 is C or N; two R.sup.1, R.sup.2, and R.sup.3 can be joined or fused to form a ring; and each R.sup.1, R.sup.2, and R.sup.3 is independently a group containing the metal M, a hydrogen, or a General Substituent defined herein. Formulations, OLEDs, and consumer products containing the compound are also provided.

A reliable light-emitting element with low driving voltage is provided. The light-emitting element includes an electron-injection layer between a cathode and a light-emitting layer. The electron-injection layer is a mixed film of a transition metal and an organic compound having an unshared electron pair. An atom of the transition metal and the organic compound form SOMO.

Disclosed is an organic light emitting diode (OLED) includes a first emitting material layer, which includes a first compound and a second compound, and a second emitting material layer, which includes a third compound and a fourth compound, wherein a HOMO energy level of the first compound is higher than a HOMO energy level of the second compound and a HOMO energy level of the third compound is lower than a HOMO energy level of the fourth compound, and an organic light emitting device having the OLED. The OLED and the organic light emitting device disclosed have enhanced luminous efficiency, color purity and luminous life span as well as low driving voltage by applying the emitting material layer.

A novel functional panel that is highly convenient, useful, or reliable is provided. The functional panel includes a pixel including a microlens array and a light-emitting device. The light-emitting device emits first light. The microlens array collects the first light. The microlens array includes a plurality of microlenses. The microlenses have a cross section having a shape with which they can be arranged with a filling factor higher than that of a circle on a plane parallel to the light-emitting device. The microlenses have a curved surface on a plane orthogonal to the plane parallel to the light-emitting device. The convex side of the curved surface faces the light-emitting device.