Tetradentate and octahedral metal complexes suitable for use as phosphorescent or delayed fluorescent and phosphorescent emitters in display and lighting applications.

A condensed cyclic compound is represented by Formula 1. A light-emitting device includes a first electrode, a second electrode facing the first electrode, and an interlayer disposed between the first electrode and the second electrode, wherein the interlayer includes an emission layer and at least one condensed cyclic compound represented by Formula 1. An electronic apparatus includes the light-emitting device.

##STR00001##

A light-emitting device including: m emitting units located between a first electrode and a second electrode; and m−1 charge generation units, each located between two neighboring emitting units among the m emitting units and including an n-type charge generation layer and a p-type charge generation layer. The m emitting units may each include an emission layer, at least one of the m emission layers comprises a first emission layer and a second emission layer that are in contact with each other, the first emission layer includes a first host, a second host, and a first dopant, the second emission layer includes a third host, a fourth host, and a second dopant, the first host and the second host form a first exciplex, the third host and the fourth host form a second exciplex, and the first dopant is a delayed fluorescence dopant, and the second dopant is a phosphorescent dopant.

A light emitting devices includes a first electrode, a hole transport region on the first electrode, a first emission layer on the hole transport region, the first emission layer to emit light of a first wavelength, a second emission layer on the hole transport region and to emit light of a second wavelength, an electron transport region on the first and second emission layers, and a second electrode on the electron transport region. The first emission layer includes a first sub-emission layer including a first hole transport host and a first sub-dopant to emit the light of the first wavelength, and a second sub-emission layer including a first electron transport and a second sub-dopant to emit the light of the first wavelength. The second emission layer includes a second hole transport host, a second electron transport host, and a second dopant to emit the light of the second wavelength.

Provided are a display substrate, and a display device. The display substrate includes a base substrate and a plurality of pixel units on the base substrate. Each of the pixel units includes a plurality of sub-pixels, the pixel units include a target pixel unit, the target pixel unit includes target sub-pixels, the target sub-pixel includes a pixel driving circuit and a light-emitting unit capable of emitting light under the drive of the pixel driving circuit, the target sub-pixel further includes a photoresistor, the photoresistor is electrically connected to the pixel driving circuit, and the resistance value of the photoresistor increases as light intensity decreases. According to the present disclosure, the pixel driving circuit includes a photoresistor, and the resistance value of the photoresistor decreases as light intensity increases. As the luminous efficiencies of sub-pixels of different colors under different light intensities are different, the photoresistor is provided to provide different resistance values under different light intensities so to adjust the resistance, and balance the luminous efficiencies of sub-pixels of different colors under different light intensities, thus improving the display effect.

Provided are a condensed cyclic compound represented by Formula 1, an organic light-emitting device including the same, and an electronic apparatus including the organic light-emitting device.

##STR00001##

The detailed description of Formula 1 is the same as described in the present specification.

A light emitting device includes: a first electrode; a hole transport region disposed on the first electrode; a first emission layer disposed on the hole transport region, and which emits light of a first wavelength; a second emission layer disposed on the hole transport region, and which emits light of a second wavelength different from the first wavelength; an electron transport region disposed on the first emission layer and the second emission layer; a second electrode disposed on the electron transport region; and a capping layer disposed on the second electrode. In exit light emitted to an upper surface of the capping layer, the exit light has a maximum intensity at an azimuth angle of about 25° to about 35°.

A white organic light emitting device comprises a first emissive layer comprising a phosphorescent emitter; a second emissive layer comprising a fluorescent emitter; and an interface layer, disposed between the first emissive layer and the second emissive layer; wherein the interface layer comprises a high energy gap material represented by Formula I, Formula II, or Formula III.

##STR00001##

Provided is a blue light emitting organic EL device having high emission efficiency and a long lifetime. This organic electroluminescent device includes one or more light emitting layers between an anode and a cathode opposite to each other, wherein at least one of the light emitting layers comprises one or more hosts selected from the indolocarbazole compounds represented by the following general formula (1) and, as a light emitting dopant, a polycyclic aromatic compound represented by the following general formula (2) or a polycyclic aromatic compound having the structure represented by the general formula (2) as a substructure, and wherein in the formulae Z is an indolocarbazole ring-containing group, X.sup.1 is O, N—Ar.sup.3, S, or Se, and Y.sup.1 is B, P, P═O, P═S, Al, Ga, As, Si—R.sup.2 or Ge—R.sup.3.

##STR00001##

An organic electroluminescence device includes a cathode, an anode and an emitting layer having an anode side and a cathode side disposed between the cathode and the anode, and a further layer next to the anode side of the emitting layer. The emitting layer contains: at least one compound with a dipole moment of less than 1.7.Math.10.sup.−30 Cm (0.5 debye), as component (1); at least one organic fluorescent compound whose onset of fluorescence is at lower energies than that of component (1) and at an energy higher than 2.6 eV; and at least one organic compound whose ionization potential in absolute values is lower than 5.33 eV and whose onset of fluorescence is at higher energies than that of component (2), as component (3).