An organic light emitting device including: a substrate; a first electrode; a second electrode; and an organic layer interposed between the first electrode and the second electrode and including an emission layer, wherein one of the first electrode and the second electrode is a reflective electrode and the other is a semitransparent or transparent electrode, and wherein the organic layer includes a layer having at least one of the compounds having at least one carbazole group, and a flat panel display device including the organic light emitting device. The organic light emitting device has low driving voltage, excellent current density, high brightness, excellent color purity, high efficiency, and long lifetime.

The present invention relates to an electroluminescence device having high luminous efficiency (for example, external quantum efficiency) and high durability and causing little chromaticity shift after device deterioration. The present invention also relates to an organic electroluminescence device material comprising a substrate having thereon a pair of electrode and at least one organic layer between the electrodes, the organic layer containing a light emitting layer, wherein the light emitting layer contains a metal complex having a group represented by formula (I).

##STR00001##

A novel substance with which an increase in life and emission efficiency of a light-emitting element can be achieved is provided. A carbazole compound having a structure represented by General Formula (G1) is provided. Note that a substituent which makes the HOMO level and the LUMO level of a compound in which a bond of the substituent is substituted with hydrogen deep and shallow, respectively is used as each of substituents in General Formula (G1) (R.sup.1, R.sup.2, Ar.sup.3, and .sup.3). Further, a subsistent which makes the band gap (Bg) and the T1 level of a compound in which a bond of the substituent is substituted with hydrogen wide and high is used as each of the substituents in General Formula (G1) (R.sup.1, R.sup.2, Ar.sup.3, and .sup.3). ##STR00001##

An organic electroluminescent device, which has a pair of electrodes and at least one organic layer including a luminescent layer between the pair of electrodes, wherein at least one layer between the pair of electrodes comprises at least one metal complex having a tridentate- or higher polydentate-chain structure ligand.

There is provided a light emitting device which enables a color display with good color balance. A triplet compound is used for a light emitting layer of an EL element that emits red color, and a singlet compound is used for a light emitting layer of an EL element that emits green color and a light emitting layer of an EL element that emits blue color. Thus, an operation voltage of the EL element emitting red color may be made the same as the EL element emitting green color and the EL element emitting blue color. Accordingly, the color display with good color balance can be realized.

The present invention provides for organometallic and organic dopants suitable for use in organic carrier transporting materials. Also provided are organic light emitting devices containing doped organic carrier transporting materials.

An organic electroluminescent device, which has a pair of electrodes and at least one organic layer including a luminescent layer between the pair of electrodes, wherein at least one layer between the pair of electrodes comprises at least one metal complex having a tridentate- or higher polydentate-chain structure ligand.

A method of forming compounds that comprise a heterocyclic carbene ligand is provided. In particular, an oxazole or a thioazole carbene are used in place of the traditional imidazole carbene. These compounds may be used in OLEDs to provide devices having improved properties, such as stability and color-tuning.

A triarylamine derivative represented by a general formula (G1) given below is provided. Note that in the formula, Ar represents either a substituted or unsubstituted phenyl group or a substituted or unsubstituted biphenyl group; ? represents a substituted or unsubstituted naphthyl group; ? represents either hydrogen or a substituted or unsubstituted naphthyl group; n and m each independently represent 1 or 2; and R.sup.1 to R.sup.8 each independently represent any of hydrogen, an alkyl group having 1 to 6 carbon atoms, or a phenyl group. ##STR00001##

Novel phosphorescent tetradentate platinum (II) compounds comprising a twisted aryl group are provided. Also provided are novel phosphorescent tetradentate platinum (II) compounds comprising an imidazo[1,2-f]phenanthridine moiety. The compounds may be used in organic light emitting devices to provide improved device efficiency, line shape and lifetime.