290results about How to "High light emitting efficiency" patented technology

The present invention provides a stable new condensed polycyclic compound which is not likely to form a molecular association. In addition, the present invention also provides an organic light-emitting element having a high light-emitting efficiency and a low drive voltage. In the condensed polycyclic compound in Claim 1 represented by the general formula [1], R1, R2 and R5 are each independently selected from a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an aryl group, and a heterocyclic group. R3 and R4 each represent an alkyl group having 1 to 4 carbon atoms. The aryl group and the heterocyclic group each may have at least one of an alkyl group, an aralkyl group, an aryl group, a heterocyclic group, an amino group, and an alkoxy group as a substituent.

A charge-transporting material contains a compound represented by the following formula (1) in an organic layer, in which the contents of specific halogen-containing compounds are 0.1% or less to the compound represented by formula (1). In formula (1), each of A¹ and A² independently represents N, —CH or —CR; R represents a substituent; L represents a single bond, an arylene group, a cycloalkylene group or an aromatic heterocyclic group; each of R¹ to R⁵ independently represents a substituent; each of n1, n2 and n3 independently represents an integer of 0 to 4; each of n4 and n5 independently represents an integer of 0 to 5; and each of p and q independently represents an integer of 1 to 4.

Provided is an organic thin film light emitting element which has achieved all of improved luminous efficiency, improved driving voltage and improved durability life. Specifically provided is a light emitting element which comprises a hole transport layer and an electron transport layer between a positive electrode and a negative electrode and emits light by means of electrical energy. The light emitting element is characterized in that: the hole transport layer of the light emitting element contains a compound represented by general formula (1); the electron transport layer contains a donor compound; and the donor compound is an alkali metal, an inorganic salt containing an alkali metal, a complex of an alkali metal and an organic substance, an alkaline earth metal, an inorganic salt containing an alkaline earth metal, or a complex of an alkaline earth metal and an organic substance. (In the formula, R¹-R²⁰ each represents one group selected from the group consisting of hydrogen, deuterium, an alkyl group, a cycloalkyl group, an amino group, an aryl group, a heterocyclic group, a heteroaryl group, an alkenyl group, a cycloalkenyl group, an alkynyl group, analkoxy group, an alkylthio group, an arylether group, an arylthioether group, a halogen, a cyano group, a —P(═O)R²⁴R²⁵ group and a silyl group; R²⁴ and R²⁵ each represents an aryl group or a heteroaryl group; and these substituents may be further substituted, or adjacent two substituents may combine together to form a ring. Meanwhile, R²¹-R²³ may be the same or different and each represents one group selected from the group consisting of an alkyl group, a cycloalkyl group, an aryl group and a heteroaryl group; and these substituents maybe further substituted.)

It has a structure in which an active layer (5) that emits light by electric current injection is sandwiched between an n-type cladding layer (4) and a p-type cladding layer (6) made of materials having a larger band gap than the active layer (5), wherein the active layer (5) is made, for example, of Cd_xZn_1−xO (0≦x<1). It is further more preferable if the cladding layers (4), (6) are made, for example, of Mg_yZn_1−yO (0≦y<1). This narrows the band gap of the ZnO materials, and an oxide semiconductor capable of being wet-etched, easy to handle with, and excellent in crystallinity can be used as a material for an active layer or a cladding layer of a semiconductor light emitting device such as a blue light emitting diode or a blue laser diode in which an active layer is sandwiched between cladding layers, so that a blue semiconductor light emitting device being excellent in light emission characteristics can be obtained.

A white organic light emitting device includes an anode, a cathode, a charge generation layer arranged between the anode and the cathode and an organic layer arrangement arranged between the anode and the cathode, the organic layer arrangement including a green light emitting layer, a blue light emitting layer, and a red light emitting layer, one of the green light emitting layer, the blue light emitting layer, and the red light emitting layer includes a first light emitting layer and second light emitting layer, the charge generation layer being arranged between the first light emitting layer and the second light emitting layer.

The present invention provides a white organic light-emitting element high in the emission efficiency. In particular, the invention provides a white organic light-emitting element that has an emission spectrum having peaks in the respective wavelength regions of red color, green color and blue color and is high in the emission efficiency.

Since a spectrum region lowest in the emission efficiency is a red region, by introducing a reddish phosphorescent material, a highly efficient white organic light-emitting element is obtained. At this time, in order to inhibit the reddish phosphorescent material from singularly emitting, as shown in FIG. 1, a distance between a second emission region 114 where a reddish phosphorescent material 124 is a luminescent material and a first emission region 113 that exhibits emission in a shorter wavelength side than the second emission region is separated. In a configuration shown in FIG.1, it is preferable to use an electron transport material in a layer 115 between the first emission region and the second emission region and more preferable to use a hole block material.

A white LED with an improved structure for high light emitting efficiency is provided. The white LED includes a light source device and a phosphor containing light emitting nanoparticles and an inorganic phosphor which emit white light by being excited by the light source.

A semiconductor light-emitting device involving the steps of: forming a first semiconductor layer; forming a light-emitting layer of superlattice structure by laminating a barrier layer being made of InY1Ga1-Y1N (Y1>/=0) and a quantum well layer being made of InY2Ga1-Y1N (Y2>Y1 and Y2>0) on the first semiconductor layer; and forming a second semiconductor layer on the light-emitting layer, an uppermost barrier layer, which will become an uppermost layer of the light-emitting layer, is made thicker than the other barrier layers. Further, at the time of forming the second semiconductor layer, an upper surface of such uppermost barrier layer is caused to disappear so that the thickness of the uppermost barrier layer becomes substantially equal to those of the other barrier layers.

A semiconductor light-emitting device and a method for manufacturing the same can include a wavelength converting layer located over at least one semiconductor light-emitting chip in order to emit various colored lights including white light. The semiconductor light-emitting device can include a base board, a frame located on the base board, the chip mounted on the base board, a transparent material layer located between the wavelength converting layer and a side surface of the chip so as to extend toward the wavelength converting layer, and a reflective material layer disposed at least between the frame and both side surfaces of the wavelength converting layer and the transparent material layer. The semiconductor light-emitting device can be configured to improve light-emitting efficiency of the chip by using the reflective material layer as a reflector, and therefore can emit a wavelength-converted light having a high light-emitting efficiency from a small light-emitting surface.

An organic compound film is composed of a hole transporting region, a first mixed region, a light emitting region, a second mixed region, and an electron transporting region that are connected to one another. With the organic compound film thus structured, the blue organic light emitting device obtained is free from interfaces between layers which are present in the conventional laminate structure. When pigment doping is added to this device structure, a white organic light emitting device is obtained. A blue or white organic light emitting device having high light emission efficiency and long lifetime is provided by this method. When this organic light emitting device is combined with color conversion layers or color filters, a full color display device that consumes less power and lasts long can be obtained.

It is an object of the present invention to provide a material having a high Tg and a wide energy gap. The present invention provides a spirofluorene derivative represented by General Formula 1. (In the formula, R¹ is any one of hydrogen, an alkyl group having 1 to 4 carbon atoms, or a group represented by General Formula 2. Each of R² and R³ is either hydrogen or an alkyl group having 1 to 4 carbon atoms and may be identical or different. R⁴ is an aryl group having 6 to 15 carbon atoms. Each of R⁵ and R⁶ is any one of hydrogen, an alkyl group having 1 to 4 carbon atoms, or an aryl group having 6 to 15 carbon atoms and may be identical or different.)

An object of the present invention is to provide a light emitting apparatus that allows it to easily control the driving of LED and has high color rendering properties.

The light emitting apparatus comprises the first light emitting device 108a that has first peak emission wavelength in blue region and emits blue light, the fluorescent material 140 that is excited by the light from the first light emitting device 108a and emits red light, the second light emitting device 108b that has second peak emission wavelength which is longer than the first peak emission wavelength and is shorter than peak emission wavelength of the fluorescent material 140, and the second light emitting device 108b that emits green light of second peak emission wavelength which is longer than the first peak emission wavelength, so as to emit light generated by blending of blue light, green light and red light to the outside.

An object of the present invention is to provide a film forming method for forming a film with reduced defect and to provide a film forming method for forming a film with a uniform quality. In addition, another object is to provide a manufacturing method of a light emitting element which can be driven with low voltage. Further, another object is to provide a manufacturing method of a light emitting element with high light emission efficiency. A film with reduced defect and a uniform quality can be formed by fixing a substrate to a substrate holding unit so that at least a part of a surface of the substrate is exposed, evaporating a vapor deposition material from an evaporation source filled with the vapor deposition material, irradiating the vapor deposition material which is evaporated with a laser beam, and depositing the vapor deposition material on the surface of the substrate.

All lights generated in an organic compound layer are not taken out towards a TFT from a cathode as a transparent electrode. For instance, the light is emitted in a lateral direction (direction parallel to the substrate surface) but the light emitted in the lateral direction is not taken out resultantly, which leads to a loss. Therefore, a light emitting device structured so as to increase the amount of light taken out in a certain direction is provided as well as a method of manufacturing this light emitting device. As a result of etching treatment, an upper edge portion of an insulator (19) is curved to have a radius of curvature, a slope is formed along the curved face while partially exposing layers (18c and 18d) of a first electrode, and a layer (18b) of the first electrode is exposed in a region that serves as a light emitting region. Light emitted from an organic compound layer (20) is reflected by the slope of the first electrode (layers 18c and 18d) to increase the total amount of light taken out in the direction indicated by the arrow in FIG. 1A.

An object is to provide a light-emitting element having high light-emission efficiency by provision of a novel fluorene derivative as represented by General Formula (G1) below.

In the formula, R¹ to R⁸ independently represent any of a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted phenyl group, or a substituted or unsubstituted biphenyl group. Further, α¹ to α⁴ independently represent any of a substituted or unsubstituted arylene group having 6 to 12 carbon atoms. Furthermore, Ar¹ and Ar² independently represent any of an aryl group having 6 to 13 carbon atoms in a ring and Ar³ represents an alkyl group having 1 to 6 carbon atoms or a substituted or unsubstituted aryl group having 6 to 12 carbon atoms. J, k, m, and n each independently represent 0 or 1.

An oxadiazole derivative represented by the following general formula (G1) is synthesized and applied to the light emitting element,

• • wherein A_m is a substituent represented by a general formula (Am1), (Am2), or (Am3); each of α, β¹, and β² represents an arylene group having 6 to 25 carbon atoms; each of A_r¹ to A_r⁶ represents an aryl group having 6 to 25 carbon atoms; each of R¹ to R³ represents hydrogen, an alkyl group having 1 to 4 carbon atoms, or an aryl group having 6 to 25 carbon atoms; and R⁴ represents an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 25 carbon atoms.

It is an object of the present invention to provide an organic light-emitting display of high light-emitting efficiency. The organic light-emitting element comprising a board, upper electrode, lower electrode, a plurality of light-emitting units placed between the upper and lower electrodes, and a charge-generating layer placed between a plurality of the light-emitting units, wherein one of the light-emitting units has a layer for emitting monochromatic light and one of the light-emitting units has a layer for emitting polychromatic light, the former unit having an equivalent or lower light-emitting efficiency than the latter unit.