266 results about "White emission" patented technology

Disclosed is an electroluminescent device comprising a cathode and anode, and therebetween, at least two light-emitting layers wherein the first layer, layer A, comprises a phosphorescent light-emitting organometallic compound comprising iridium and an isoquinoline group and a second layer, layer B, comprising a light-emitting material. Such devices provide useful white light emissions.

An organic electroluminescent device such as a light-emitting diode is disclosed, in which the emission layer comprises a single emitting material at different aggregate state to obtain constant chromaticity white emission. Correspondingly, a novel configuration has been developed to get white emission and color change in the organic EL devices.

The present invention relates to efficient organic light emitting devices (OLEDs). More specifically, the present invention relates to white-emitting OLEDs, or WOLEDs. The devices of the present invention employ two emitters in a single emissive region to sufficiently cover the visible spectrum. White emission is achieved from two emitters in a single emissive region through the formation of an aggregate by one of the emissive centers. This allows the construction of simple, bright and efficient WOLEDs that exhibit a high color rendering index.

The present invention relates to efficient organic light emitting devices (OLEDs). More specifically, the present invention relates to white-emitting OLEDs, or WOLEDs. The devices of the present invention employ two emitters in a single emissive region to sufficiently cover the visible spectrum. White emission is achieved from two emitters in a single emissive region through the formation of an aggregate by one of the emissive centers. This allows the construction of simple, bright and efficient WOLEDs that exhibit a high color rendering index.

A white light emitting apparatus includes a light source section in which a first white LED that emits white light whose chromaticity deviates to a blue side from a predetermined white region of a CIE chromaticity diagram and a second white LED that emits white light whose chromaticity deviates to a yellow side from the predetermined white region are adjacently disposed so as to emit light with optical axes in substantially the same direction, and a current regulator that independently drives the blue LED chip in the first and second white LEDs, respectively. A color mixture of lights emitted from the first and second white LEDs is adjusted to a chromaticity of the predetermined white region using the current regulator.

Provided herein are novel phosphors useful in the manufacture of white light emitting diodes. The phosphors provided by the invention are described by the formula: SrxBayCazSiO4:Eu in which x, y, and z are each independently variable to be any value between about 0 and about 2, including without limitation 0.001 and 2, and every thousandth therebetween, subject to the proviso that the sum of x, y, or z is equal to at least 1, and in which Eu is present in any amount between about 0.0001% and about 5% by weight based upon the phosphor's total weight, wherein substantially all of the europium present is present in the divalent state. A phosphor according to the invention may optionally further comprise an element selected from the group consisting of: Ce, Mn, Ti, Pb, and Sn and is present in any amount between about 0.0001% and about 5% by weight based on the phosphor's total weight. The silicate phosphor materials provided by the present invention do not require the addition of dissimilar blue and red phosphor compounds, and do not contain zinc and/or magnesium. In addition, the present invention provides materials which emit a broad yellowish color containing both green and red emissions. Standard techniques used in phosphor deposition for the manufacture of light emitting diodes which comprise phosphors may be employed to produce LED's having a white light output when the phosphors of the invention are utilized.

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 tunable colour LED module comprises at least two sub-modules, each comprising an LED (104), a wavelength converting element (WCE) (201, 112, 203) and a reflector cup. The total light emitted by the module comprises light generated from each LED and WCE and the module is configured to emit a total light having a predefined colour chromaticity when activation properties of the LEDs are managed appropriately. The total light may have a broad white emission spectrum (106). The module combines the benefits of a low cost with uniform chromaticity properties in the far field, and offers long and controlled lifetime at the same time as flexibility and intelligence of tunable colour chromaticity, Colour Rendering Index (CRI) and intensity, either at manufacture or in an end user lighting application. A controlled LED module system comprises a control system for the managing activation properties of the LEDs in the sub-modules. Also described is a method of manufacture.

A fluorescent material excellent in emission efficiency in white emission and a light-emitting apparatus employing this fluorescent material and having excellent color rendering are provided with a fluorescent material comprising a two-layer structure of a core of a particle size having a quantum effect and a shell covering this core in which the ground state energy of the core is in the range of 1.85 to 2.05 eV, the high order energy of the core is not in the ranges of 2.3 to 2.5 eV and 2.65 to 2.8 eV, or the ground state energy of the core is in the range of 2.3 to 2.5 eV, the high order energy of the core is not in the range of 2.65 to 2.8 eV an light-emitting apparatus employing these fluorescent materials.

Provided are a phosphor, a phosphor manufacturing method, and a white light emitting device. The phosphor is represented as a chemical formula of aMO-bAl₂O₃-cSi₃N₄, which uses light having a peak wavelength in a wavelength band of about 350 nm to about 480 nm as an excitation source to emit visible light having a peak wavelength in a wavelength band of about 480 nm to about 680 nm. (where M is one kind or two kinds of elements selected from Mg, Ca, Sr, and Ba (0.2≦a/(a+b)≦0.9, 0.05≦b/(b+c)≦0.85, 0.4≦c/(c+a)≦0.9))

To improve power efficiency of a light-emitting element for white emission even when light in a wavelength range of low luminosity is utilized. As a light-emitting element for white emission, three light-emitting layers are stacked. In such a light-emitting element, the three light-emitting layers are included between a light-transmitting electrode and a light-reflecting electrode, and light emitted from each light-emitting layer is reflected on the light-reflecting electrode and is transmitted through the light-transmitting electrode. In addition, the light-emitting layer closer to the light-reflecting electrode has a shorter optical path length. Thus, the position of each light-emitting layer is limited depending on the distance from the light-reflective electrode, and the optical path length of each light-emitting layer is adjusted; therefore the light-emitting element with high power efficiency can be provided.

Disclosed is a high-efficiency, long-life white-emission organic electroluminescent element, in particular, a white-emission organic electroluminescent element. The organic electroluminescent element of the present invention has a red phosphorescent light emitting-layer 12; a green phosphorescent light emitting-layer 11; a blue fluorescent light-emitting layer 22 and a green fluorescent light-emitting layer 21. A phosphorescent light unit 1 is formed by the red phosphorescent light emitting-layer 12 and the green phosphorescent light emitting-layer 11. A fluorescent light unit 2 is formed by the blue fluorescent light-emitting layer 22 and the green fluorescent light-emitting layer 21. The phosphorescent light unit 1 and the fluorescent light unit 2 are connected via an interlayer 3. Preferably, the phosphorescent light unit 1 is disposed further towards a cathode 4a side than the fluorescent light unit 2. Preferably, the emission color is any of a W color, a WW color and an L color.

PROBLEM TO BE SOLVED: to realize a wide bandwidth light source capable of a stable operation providing a less spectrum variation.

SOLUTION: Optical pulses 202 outputted by this optical pulse-generating device 201 are split by optical coupler 210. The one of split optical pulses is inputted in white light-emitting device 204 to emit the white light having the wide bandwidth. The other split is inputted in optical band pass filter 212 in operation-stabilizing circuit 207. Optical detector 213 detects a signal level of a specific wavelength and input in feedback circuit 215 to generate first and second feedback signals 205 and 206. Ring resonator fiber laser 208 uses any one of them and controls a rotation angle of the waveplate to realize stabilization of the output.

Organic light-emitting diodes (OLEDs) that produce white light include an anode, a hole-transporting layer disposed over the anode, a blue light-emitting layer disposed over the hole-transporting layer, an electron-transporting layer disposed over the blue light-emitting layer, and a cathode disposed over the electron-transporting layer. The hole-transporting layer is doped with both a yellow-emitting and a red-emitting dopant. When used together with red, green, and blue color filters, the OLEDs produce red, green, and blue light with good color quality and high efficiency. Also disclosed are multicolor display devices utilizing the OLEDs together with color filters or together with both color filters and liquid-crystal light valves.

A white light emitting device includes a structure for emitting white light having at least four wavelengths by using two or less LEDs, where the LEDs include a blue/green LED emitting blue and green wavelengths of light. The device also includes means for emitting red wavelength of light.

A white-light emitting device includes a first die and a second die. The first die has a first semiconductor light-emitting layer emitting a first primary color light. The second die has a second semiconductor light-emitting layer emitting a second primary color light, and a third semiconductor light-emitting layer mounted proximate to the second semiconductor light-emitting layer and emitting a third primary color light. The first primary color light is combined with the second and third primary color lights so as to produce white light.

A white-light-emitting tandem OLED device having spaced anode and cathode including: first and second light-emitting units disposed between the anode and cathode; an intermediate connector including an n-type layer and a p-type layer disposed between the first and second light-emitting units; and a fluoranthene-containing electron-transporting layer adjacent to the n-type layer of the intermediate connector and including at least 25% of a 7,10-diaryl-substituted fluoranthene compound having no aromatic rings annulated to the fluoranthene nucleus.