358results about How to "Reduced luminous efficiency" patented technology

A method for manufacturing a light-emitting diode, which includes the steps of: providing a substrate having a plurality of protruded portions on one main surface thereof wherein the protruded portion is made of a material different in type from that of the substrate and growing a first nitride-based III-V Group compound semiconductor layer on each recess portion of the substrate through a state of making a triangle in section wherein a bottom surface of the recess portion becomes a base of the triangle; laterally growing a second nitride-based III-V Group compound semiconductor layer on the substrate from the first nitride-based III-V Group compound semiconductor layer; and successively growing, on the second nitride-based III-V Group compound semiconductor layer, a third nitride-based III-V Group compound semiconductor layer of a first conduction type, an active layer, and a fourth nitride-based III-V compound semiconductor layer of a second conduction type.

An object is to provide an organometallic complex that can emit red light. Another object is to provide an organometallic complex having high emission efficiency. Still another object is to provide an organometallic complex that can emit red light with high luminous efficiency. The present invention provides an organometallic complex having a structure represented by the following general formula (G1′).

In the formula, Ar represents an aryl group having 6 to 25 carbon atoms; R¹ represents any one of hydrogen, an alkyl group having 1 to 4 carbon atoms, and an alkoxy group having 1 to 4 carbon atoms; R² to R⁸ each represent any one of hydrogen, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, and a halogen group; at least one of pairs R³ and R⁴, R⁴ and R⁵, and R⁵ and R⁶ may be bound to each other to form a ring; and M represents a central metal of Group 9 elements and Group 10 elements.

A light-emitting diode which has a significantly high luminous efficiency and which can be manufactured at a reasonable cost by one epitaxial growth and a manufacturing method thereof are provided. The above method includes: preparing a substrate provided with convex portions on one major surface, the convex portions being formed from a dielectric substance which is different from the substrate and which has a refractive index of 1.7 to 2.2; growing a first nitride-based III-V compound semiconductor layer in a concave portion on the substrate; growing a second nitride-based III-V compound semiconductor layer on the substrate from the first nitride-based III-V compound semiconductor layer in a lateral direction; and growing, on the second nitride-based III-V compound semiconductor layer, a first conductive type third nitride-based III-V compound semiconductor layer, an active layer, and a second conductive type fourth nitride-based III-V compound semiconductor layer.

A backlight device that illuminates a transmissive liquid crystal panel is disclosed. The device includes: a plurality of light source substrates on which a plurality of light emitting devices irradiating illumination light are mounted; a bottom chassis having one surface to which the plurality of light source substrates are attached; a reflector having openings corresponding to the light emitting devices and through which the light emitting devices are exposed to one surface side, and reflecting the illumination light irradiated from the light emitting devices; a diffuser facing the one surface side of the reflector through a predetermined facing interval and internally diffusing the illumination light incident from the reflector; and an optical function sheet laminate combined with the diffuser on one surface side thereof, containing a stack of a plurality of optical function sheets and guiding the illumination light to the transmissive liquid crystal panel.

An automotive discharge bulb having a light emitting tube includes a ceramic tube with paired electrodes oppositely placed, and contains a light emitting material and starting rare gas. A transversal section of the ceramic tube is longitudinally elongated. Because the capacity of an enclosed space of the ceramic tube is small, after discharging begins, the enclosed space temperature increases. Consequently, the ceramic tube has a good luminous flux rising characteristic. Because of the small surface area of the ceramic tube, the load imposed on the wall surface increases. Consequently, the ceramic tube has good luminous efficiency. In the ceramic tube having a longitudinally elongated transversal section, an arc generated into an upwardly convex shape and the tube wall do not make contact. Thermal shock resistance required of the ceramic tube is alleviated, durability is enhanced, and the ceramic tube is made of a ceramic material hitherto unusable.

An image capturing device employing as illumination source(s) (flash apparatus(es)) a plurality of light emitting diodes emitting light of different colors; wherein such light emitting diodes are respectively made to emit light in pulsed fashion in turn by emitted color during exposure time(s). Furthermore, during exposure time(s), such light emitting diodes may be made to sequentially emit light in pulsed fashion in turn by emitted color, and/or such light emitting diodes may be made to sequentially emit light in pulsed fashion in turn by emitted color over multiple iterations.

A vehicular headlamp, wherein a light source unit for light distribution formation is accommodated inside a lamp chamber defined by a lamp body and a front cover, includes a metal heat transfer member that serves as a light source unit structural member; a light-emitting element that serves as a light source; a fan for cooling the light-emitting element provided inside the lamp chamber; and a lighting circuit that controls lighting of the light-emitting element. The light-emitting element, the fan, and the lighting circuit are each attached to the metal heat transfer member.

A semiconductor light emitting device may include an n-type contact layer on a substrate. An active layer may be on the n-type contact layer and/or include two or more quantum well layers and two or more barrier layers. A p-type contact layer may be on the active layer. Energy band gaps of the quantum well layers may be larger as the quantum well layers are closer to the n-type contact layer from the p-type contact layer, thicknesses of the quantum well layers may be smaller as the quantum well layers are closer to the n-type contact layer from the p-type contact layer, and/or energy band gaps of the barrier layers may be larger as the barrier layers are closer to the n-type contact layer from the p-type contact layer.

An organic electroluminescence device including opposite anode and cathode, and a hole-transporting region, an emitting layer and an electron-transporting region in sequential order from the anode between the anode and the cathode, wherein the emitting layer is formed of a red emitting layer, a green emitting layer, and blue emitting layer; the blue emitting layer contains a host BH and a fluorescent dopant FBD; the triplet energy E^T_fbd of the fluorescent dopant FBD is larger than the triplet energy E^T_bh of the host BH; the green emitting layer contains a host GH and a phosphorescent dopant PGD; a common electron-transporting layer is provided adjacent to the red emitting layer, the green emitting layer and the blue emitting layer within the electron-transporting region; the triplet energy E^T_el of a material constituting the electron-transporting layer is larger than E^T_bh; and the difference between the affinity of the host GH and the affinity of the material constituting the electron-transporting layer is 0.4 eV or less.

A headlamp (1) includes a laser diode (2) for emitting a laser beam and a light-emitting section (5), which contains a fluorescent substance for emitting fluorescence upon receiving the laser beam emitted from the laser diode (2) and diffusing particles (15) for diffusing the laser beam.

The invention increases the outgoing efficiency of light generated in an organic luminous layer of an organic electroluminescence element without decreasing the numerical aperture. A light-transmissive anode electrode layer, an organic luminous layer, and a light-reflective cathode layer are provided on the entire surface of one pixel region. On the anode layer, the organic luminous layer, and the cathode layer, slopes are installed protruding from the anode layer side to the cathode layer side. By this, light generated in the organic luminous layer, and irradiated in parallel to a cumulate surface of a cumulate body, is reflected by the slope on the boundary between the organic luminous layer and the cathode layer and exits toward the anode layer side.

Provided are a photonic crystal type color filter and a reflective liquid crystal display (“LCD”) device having the same. The photonic crystal type color filter includes a substrate, and a photonic crystal disposed on the substrate and having a two-dimensional (2D) grating structure.

White LED device 20 includes LED chip 13 mounted on substrate 1 made of metal, sealing resin 11 that seals LED chip 13; and glass member 12 formed on sealing resin 11. Glass member 12 contains phosphor 22 and thermal conductivity of sealing resin 11 is lower than that of glass member 12.

A light emitting diode (LED) driving apparatus includes a drive section for driving an LED to emit light, and a control section that controls a driving current supplied from the drive section to the LED. The control section implements luminous power control by controlling an ON/OFF ratio of the driving current if a target value of luminous power of the LED is smaller than a predetermined value. The control section implements luminous power control by controlling a level of the driving current if the target value is equal to or larger than the predetermined value.

The present invention relate to a liquid crystal display device using a light emitting diode (LED) module as a light source for backlight. Storing portions (21a-21e) are provided at positions facing a light emitting diode modules (25) on a light guide plate (21) constituting the backlight, and the light emitting diode modules (25) are inserted into the storing portions (21a-21e). Furthermore, under a status where an insulating substrate (26) mounted with the light emitting diode modules (25) is held by a holding plate (28), the holding plate (28) is removably attached to a heat sink substrate (27). The backlight has a structure wherein the light emitting diode module (25) can be replaced. Furthermore, since heat generated at the light emitting diode module (25) can be efficiently dissipated to the heat sink substrate (27), temperature increase of the light emitting diode module (25) is suppressed, and lifetime can be lengthened, and deterioration of luminous efficiency can be prevented.

A lighting fixture, which is arranged to receive two or more elongated light sources positioned one after another in the longitudinal direction of the light sources, the lighting fixture comprising one or more connecting devices, which are arranged to supply energy to the light sources in order to burn them and positioned in a region between the successive light sources in the lighting fixture, and a globe part and a background part, which are arranged to be connected to one another and to substantially surround the light sources and the connecting devices. The lighting fixture further comprises one or more cover plates, which are arranged at the connecting devices between the globe part and the background part of the lighting fixture to substantially cover the connecting devices, and one or more second light sources, which are arranged in connection with the cover plate to provide lighting from the region between the successive elongated light sources.

an anisotropic conductive adhesive which uses conductive particles where a silver-based metal is used as a conductive layer, having high light reflectance and excellent migration resistance is provided. The anisotropic conductive adhesive includes light reflective conductive particles in an insulating adhesive resin. The light reflective conductive particle includes a light reflective metal layer made of a metal alloy including silver, gold and hafnium formed on the surface of a resin particle as a core by sputtering method. The light reflective metal layer is preferably formed having a composition ratio of a silver of at least 50% by weight to at most 80% by weight: a gold of at least 10% by weight to at most 45%: a hafnium of at least 10% by weight to at most 40% by weight, and a total ratio does not exceed 100% by weight.

The invention discloses a condensed-ring compound and a preparation method and an application thereof. The condensed-ring compound has a structure represented by formula (I) or formula (II). The HOMOand LUMO energy levels of the fused-ring compound are completely separated, so that the energy gap width of the material is reduced, the three-wire energy level is improved, and the energy backflow from the object material to the main material is avoided to reduce the luminous efficiency; HOMO and LUMO energy levels are matched with adjacent materials, and the driving voltage is small. The devicehas large molecular structure size and good intramolecular conjugation, so it has good thermal stability, can avoid thermal decomposition of materials during film formation or use, avoids loss of material layer function, and improves luminous efficiency and luminous performance of the device. The invention also provides a preparation method of the fused-ring compound and its application as an organic electroluminescent material.

An organic EL display device including organic EL light-emitting regions which includes a red-light emitting layer, a green-light emitting layer, and a blue-light emitting layer that are arranged on a main substrate includes: a first light-adjusting layer including a first portion and a second portion, the first portion selectively transmitting desired blue light, and the second portion absorbing visible light other than at least the desired blue light; and a second light-adjusting layer selectively absorbing light with a wavelength between desired red light and desired green light at an entire surface, in which the blue light-emitting layer is overlaid with the first portion, and a bank which is a non-light emitting portion is overlaid with the second portion. The first portion and the second portion may be integrally formed of a same material, and the second portion may absorb an entire range of visible light.