A white light emitting device comprises: an LED that generates excitation light of wavelength from 420 nm to 480 nm; and photoluminescence materials that generate light with a peak emission wavelength from 500 nm to 650 nm comprising a broadband phosphor, and a manganese-activated narrowband red fluoride phosphor with a peak emission wavelength from 628 nm to 640 nm and a full width at half maximum of less than 30 nm. The device generates white light with a selected color temperature from 2200K to 6500K, a General Color Rendering Index, CRI Ra, of at least 80, and a Duv (Delta u, v) from 0.0060 to 0.0170 for the selected color temperature and wherein the device has an LER (Luminous Efficacy of Radiation) of at least 320 lm/W.sub.opt.

Disclosed is a new class of photo-responsive coordination compounds with at least one photochromic unit on a coordinating ligand. The photo-responsive coordination compounds are shown to be capable of acting as electroactive materials for the fabrication of organic memory devices as well as photo-controllable electron-transporting materials.

A metallic compound for use in an electronic apparatus having an organic light emitting element, the metallic compound having a refractive index: n.sub.620 nm≤about 1.60; n.sub.530 nm≤about 1.65; and n.sub.460nm≤about 1.68.

A fluorescent labeling agent contains a fluorescent dye represented by general formula (1). General formula (1): Q-Z—R.sub.1-R.sub.2-R.sub.3 (In the formula, Q represents the residue of a fluorescent dye. Z represents a direct bond, alkylene group, or arylene group. R.sub.1 represents a direct bond, —O—, —OP(═O)R.sub.4—, —OC(═O)—, —OS(═O).sub.2—, —OSiR.sub.5R.sub.6—, —C(═O)—, or —C(═O)NH—. R.sub.2 represents a group selected from the group consisting of alkylene groups, arylene groups, and heterocyclic groups, or represents a group provided by combining these groups. R.sub.3 represents —COOM.sub.1, —NR.sub.7R.sub.8, or —N.sup.+R.sub.9R.sub.10R.sub.11. Here, R.sub.4 represents a hydrogen atom, hydroxyl group, alkyl group, aryl group, alkoxy group, aryloxy group, or heterocyclic group. R.sub.5 and R.sub.6 each independently represent an alkyl group, aryl group, or heterocyclic group. R.sub.7-R.sub.11 each independently represent a hydrogen atom, alkyl group, or aryl group. M.sub.1 represents a monovalent cation.)

Organic light emitting devices are described wherein the emissive layer comprises a host material containing an emissive molecule, which molecule is adapted to luminesce when a voltage is applied across the heterostructure, and the emissive molecule is selected from the group of phosphorescent organometallic complexes, including cyclometallated platinum, iridium and osmium complexes. The organic light emitting devices optionally contain an exciton blocking layer. Furthermore, improved electroluminescent efficiency in organic light emitting devices is obtained with an emitter layer comprising organometallic complexes of transition metals of formula L.sub.2MX, wherein L and X are distinct bidentate ligands. Compounds of this formula can be synthesized more facilely than in previous approaches and synthetic options allow insertion of fluorescent molecules into a phosphorescent complex, ligands to fine tune the color of emission, and ligands to trap carriers.

An organometallic compound represented by Formula I, an organic light-emitting device including the same, and a diagnostic composition including the organometallic compound. ##STR00001##

An organic light-emitting device includes: a first electrode; a second electrode facing the first electrode; and an organic layer between the first electrode and the second electrode, the organic layer including an emission layer. The organic layer includes a first compound represented by Formula 1 and a second compound represented by Formula 2. The first compound may be included in an emission layer, and the second compound may be included in an electron transport region.

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An organic electroluminescent device having an anode, a cathode, and a light emitting layer between the anode and the cathode, in which the light emitting layer contains a first organic compound, a second organic compound, and a third organic compound that satisfy the following expression (A), the second organic compound is a delayed fluorescent material, and the third organic compound is a light emitting material, is capable of enhancing the light emission efficiency. E.sub.S1(A), E.sub.S1(B) and E.sub.S1(C) represent a lowest, singlet excitation energy level of the first, second and third organic compound, respectively.

E.sub.S1(A)>E.sub.S1(B)>E.sub.S1(C)   (A)

An organic electroluminescent device having an anode, a cathode, and a light emitting layer between the anode and the cathode, in which the light emitting layer contains a first organic compound, a second organic compound, and a third organic compound that satisfy the following expression (A), the second organic compound is a delayed fluorescent material, and the third organic compound is a light emitting material, is capable of enhancing the light emission efficiency. E.sub.S1(A), E.sub.S1(B) and E.sub.S1(C) represent a lowest singlet excitation energy level of the first, second and third organic compound, respectively.
E.sub.S1(A)>E.sub.S1(B)>E.sub.S1(C)  (A)

An organic light-emitting device includes: a first electrode; a second electrode facing the first electrode; and an organic layer between the first electrode and the second electrode, the organic layer including an emission layer. The organic layer includes a first compound represented by Formula 1 and a second compound represented by Formula 2. The first compound may be included in an emission layer, and the second compound may be included in an electron transport region. ##STR00001##