Abstract: A mobile communication system, according to the present invention includes: a cell station; and a plurality of mobile stations, which are connectable to the cell station in wireless manner. Each of the mobile stations calculates a transmission timing of link channel request for communication with the cell station in accordance with a formula using a parameter, which is calculated using a random number.

Abstract: It is an object of the present invention to provide a novel material that can be used for an electron injecting material. In addition, it is an object of the present invention to provide a light-emitting element that is able to broaden choices for an electrode material. An aspect of the present invention is an electron injecting material represented by a general formula (2). In the general formula (2), R6 is selected from the group consisting of an alkyl group having 1 to 4 carbon atoms, an alkenyl group having 1 to 4 carbon atoms, and an aryl group having 6 to 10 carbon atoms, where the alkenyl group and the aryl group may have a substituent.

Abstract: The present invention provides a light-emitting element sandwiching a composite layer in which an organic compound and an inorganic compound are mixed between a first electrode and a second electrode, where the composite layer includes a first layer including a first organic compound and a first inorganic compound that exhibits an electron accepting property to the first organic compound (serves as an electron acceptor), a second layer including a second organic compound and a second inorganic compound, and a third layer including a third organic compound and a third inorganic compound that exhibits an electron donating property to the third organic compound (serves as an electron acceptor).

Abstract: It is an object of the present invention to provide a light-emitting element having a structure in which the drive voltage is relatively low. Further, it is an object of the invention to provide a highly reliable light emitting device by alleviating the stress to the light emitting layer. Further, it is another object of the invention to provide a light emitting element having a structure in which increase in the drive voltage over time is small. It is an object of the present invention to provide a display device in which the drive voltage is low and increase in the drive voltage over time is small and which can withstand long-term use.

Abstract: It is an object to provide a light emitting element that has a different structure from that of a conventional light emitting element and includes a substance having a novel structure. It is also an object to provide a light emitting device having the light emitting element. In the view of the objects described above, the present invention provides a light emitting element including a layer containing a triazine derivative represented by the general formula (1) and a metal oxide that is an inorganic compound, provided between a pair of electrodes. Further, the present invention provides a light emitting device that has the light emitting element.

Abstract: It is an object of the present invention to provide a light emitting element which can reduce defective operation due to crystallization of a compound. One of the light emitting elements of the present invention has a layer, which generates electrons, between a first electrode and a second electrode. The layer generating electrons includes a phenanthroline derivative represented by the general formula (1) and a metal oxide. The metal oxide shows an electron donating property to the phenanthroline derivative represented by the general formula (1). Herein, in the general formula (1), R1 to R5 individually represents an alkyl group having 1 to 4 carbon atoms or a halogen group, and further at least one of R1 to R5 represents a halogen group.

Abstract: An object is to provide a light emitting element with low drive voltage which contains an organic compound and an inorganic compound. One feature of a light emitting element of the present invention is to include a layer containing a light emitting material between a pair of electrodes, in which the layer containing a light emitting material has a layer containing a carbazole derivative represented by General Formula (1) and an inorganic compound which exhibits an electron accepting property to the carbazole derivative represented by General Formula (1). With such a structure, the inorganic compound accepts electrons from the carbazole derivative, carriers are generated internally, and a drive voltage of the light emitting element can be reduced.

Abstract: A light emitting element of the invention includes n pieces of light emitting layers (n is a natural number) between first and second electrodes. A first layer and a second layer are provided between the mth light emitting layer (m is a natural number of 1?m?n) and the m+1th light emitting layer. The first and second layers are contacted to each other. The first layer contain a substance that transports holes easily and a substance with an electron accepting property. The second layer contains a substance that transports electrons easily and a substance with an electron donating property. Molybdenum oxide is used as the substance with the electron accepting property.

Abstract: An object is to provide a light emitting element with low drive voltage which contains an organic compound and an inorganic compound. One feature of a light emitting element of the present invention is to include a layer containing a light emitting material between a pair of electrodes, in which the layer containing a light emitting material has a layer containing a carbazole derivative represented by General Formula (1) and an inorganic compound which exhibits an electron accepting property to the carbazole derivative represented by General Formula (1). With such a structure, the inorganic compound accepts electrons from the carbazole derivative, carriers are generated internally, and a drive voltage of the light emitting element can be reduced.

Abstract: Light-emitting elements have a problem that their light-extraction efficiency is low due to scattered light or reflected light inside the light-emitting elements. The light-extraction efficiency of the light-emitting elements needs to be enhanced by a new method. According to the present invention, a light-emitting element includes a first layer generating holes, a second layer including a light-emitting layer for each emission color and a third layer generating electrons between an anode and a cathode, and the thickness of the first layer is different depending on each layer including the light-emitting layer for each emission color. A layer in which an organic compound and a metal oxide are mixed is used as the first layer, and thus, the driving voltage is not increased even when the thickness is increased, which is preferable.

Abstract: It is an object of the present invention to provide a light-emitting element capable of reducing malfunction due to oxidation and crystallization of a compound. According to one aspect of the present invention, a light-emitting element has a first electrode and a second electrode, a first layer and a second layer formed between the first electrode and the second electrode, wherein the first layer contains an anthracene derivative and a substance that shows electron acceptability to the anthracene derivative, wherein the second layer contains a light emitting substance. According to one aspect of a light-emitting device of the present invention, any one of the above light-emitting elements is used as a pixel or a light source.

Abstract: An object is to provide a light emitting element with low drive voltage which contains an organic compound and an inorganic compound. One feature of a light emitting element of the present invention is to include a layer containing a light emitting material between a pair of electrodes, in which the layer containing a light emitting material has a layer containing a carbazole derivative represented by General Formula (1) and an inorganic compound which exhibits an electron accepting property to the carbazole derivative represented by General Formula (1). With such a structure, the inorganic compound accepts electrons from the carbazole derivative, carriers are generated internally, and a drive voltage of the light emitting element can be reduced.

Abstract: An object of the invention is to provide a highly reliable light emitting element with low drive voltage and longer life than a conventional light emitting element, and a display device using the light emitting element. A light emitting element according to the invention comprises a plurality of layers which is interposed between a pair of electrodes, in which at least one of the plurality of layers is formed of a layer containing a light emitting material, and the layer containing a light emitting material is interposed between a layer containing an oxide semiconductor and/or metal oxide and a material having a higher hole transporting property than an electron transporting property, and a layer containing an oxide semiconductor and/or metal oxide, a material having a higher electron transporting property than a hole transporting property and a material which can donate electrons to the material having a higher electron transporting property than a hole transporting property.

Abstract: The present invention provides a light-emitting element having less increase in driving voltage with the accumulation of light-emission time, and provides a light-emitting element having less increase in resistance value with the increase in film thickness. A light-emitting element includes a first layer, a second layer and a third layer between a first electrode and a second electrode. The first layer is provided to be closer to the first electrode than the second layer, and the third layer is provided to be closer to the second electrode than the second layer. The first layer is a layer including an aromatic amine compound and a substance showing an electron accepting property to the aromatic amine compound. The second layer includes a substance of which an electron transporting property is stronger than a hole transporting property, and a substance showing an electron donating property to the aforementioned substance.

Abstract: Light-emitting elements have a problem that their light-extraction efficiency is low due to scattered light or reflected light inside the light-emitting elements. The light-extraction efficiency of the light-emitting elements needs to be enhanced by a new method. According to the present invention, a light-emitting element includes a first layer generating holes, a second layer including a light-emitting layer for each emission color and a third layer generating electrons between an anode and a cathode, and the thickness of the first layer is different depending on each layer including the light-emitting layer for each emission color. A layer in which an organic compound and a metal oxide are mixed is used as the first layer, and thus, the driving voltage is not increased even when the thickness is increased, which is preferable.

Abstract: A light emitting element of the invention includes n pieces of light emitting layers (n is a natural number) between first and second electrodes. A first layer and a second layer are provided between the mth light emitting layer (m is a natural number of 1?m?n) and the m+1th light emitting layer. The first and second layers are contacted to each other. The first layer contains a substance that transports holes easily and a substance with an electron accepting property. The second layer contains a substance that transports electrons easily and a substance with an electron donating property. Molybdenum oxide is used as the substance with the electron accepting property.

Abstract: To provide an electrode for an organic device which can be widely applied to organic devices by having both hole injection function and electron injection function. A carrier injection electrode layer 110 in which a metal for electron injection 112 (a metal having a work function of 4.2 eV or less) and a metal for hole injection 113 (a metal having a work function of more than 4.2 eV) are mixed with one kind of organic compound 111 is provided between a first organic layer 100a and a second organic layer 100b. Thus, carriers are injected into a carrier injection electrode layer 110 in the direction according to voltage application, and seemingly, current flows between an organic layer 100 and a metal electrode 101, or between the first organic layer 100a and the second organic layer 100b.

Abstract: An object of the invention is to provide a highly reliable light emitting element with low drive voltage and longer life than a conventional light emitting element, and a display device using the light emitting element. A light emitting element according to the invention comprises a plurality of layers which is interposed between a pair of electrodes, in which at least one of the plurality of layers is formed of a layer containing a light emitting material, and the layer containing a light emitting material is interposed between a layer containing an oxide semiconductor and/or metal oxide and a material having a higher hole transporting property than an electron transporting property, and a layer containing an oxide semiconductor and/or metal oxide, a material having a higher electron transporting property than a hole transporting property and a material which can donate electrons to the material having a higher electron transporting property than a hole transporting property.

Abstract: The present invention provides a light-emitting element having less increase in driving voltage with the accumulation of light-emission time, and provides a light-emitting element having less increase in resistance value with the increase in film thickness. A light-emitting element includes a first layer, a second layer and a third layer between a first electrode and a second electrode. The first layer is provided to be closer to the first electrode than the second layer, and the third layer is provided to be closer to the second electrode than the second layer. The first layer is a layer including an aromatic amine compound and a substance showing an electron accepting property to the aromatic amine compound. The second layer includes a substance of which an electron transporting property is stronger than a hole transporting property, and a substance showing an electron donating property to the aforementioned substance.

Abstract: A layer included in an electroluminescent element is required to be thickened to optimize light extraction efficiency of the electroluminescent element and to prevent short-circuit between electrodes. However, in a conventional element material, desired light extraction efficiency cannot be accomplished since drive voltage rises or power consumption is increased as the element material is thickened. A composite is formed by mixing a conjugated molecule having low ionization potential and a substance having an electron-accepting property to the conjugated molecule. A composite layer included in an element is formed using the composite as an element material. The composite layer is arranged between a first electrode and a light emitting layer or between a second electrode and a light emitting layer. The composite layer has high conductivity; therefore, drive voltage does not rise even if a film thickness is increased.