2684 results about "Europium" patented technology

The invention relates to a light source comprising a light-emitting element, which emits light in a first spectral region, and comprising a luminophore, which comes from the group of alkaline-earth orthosilicates and which absorbs a portion of the light emitted by the light source and emits light in another spectral region. According to the invention, the luminophore is an alkaline-earth orthosilicate, which is activated with bivalent europium and whose composition consists of: (2-x-y)SrOx(Ba, Ca)O(1-a-b-c-d)SiO2aP2O5bAl2O3cB2O3dGeO2:yEu<2+> and / or (2-x-y)BaOx((Sr, Ca)O(1-a-b-c-d)SiO2aP2O5bAl2O3cB2O3dGeO2:yEu<2+>. The desired color (color temperature) can be easily adjusted by using a luminophore of the aforementioned type. The light source can contain an additional luminophore selected from the group of alkaline-earth aluminates, activated with bivalent europium and / or manganese, and / or can contain an additional red-emitting luminophore selected from the group Y(V, P, Si)O4:Eu or can contain alkaline-earth magnesium disilicate.

A phosphor comprises: (a) at least a first metal selected from the group consisting of yttrium and elements of lanthanide series other than europium; (b) at least a second metal selected from the group consisting of aluminum, gallium, indium, and scandium; (c) boron; and (d) europium. The phosphor is used in light source that comprises a UV radiation source to convert UV radiation to visible light.

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:Euin 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.

Embodiments of the present invention are directed to nitride-based, red-emitting phosphors in red, green, and blue (RGB) lighting systems, which in turn may be used in backlighting displays and warm white-light applications. In particular embodiments, the red-emitting phosphor is based on CaAlSiN3 type compounds activated with divalent europium. In one embodiment, the nitride-based, red emitting compound contains a solid solution of calcium and strontium compounds (Ca,Sr)AlSiN3:Eu2+, wherein the impurity oxygen content is less than about 2 percent by weight. In another embodiment, the (Ca,Sr)AlSiN3:Eu2+ compounds further contains a halogen in an amount ranging from about zero to about 2 atomic percent, where the halogen may be fluorine (F), chlorine (Cl), or any combination thereof. In one embodiment at least half of the halogen is distributed on 2-fold coordinated nitrogen (N2) sites relative to 3-fold coordinated nitrogen (N3) sites.

An inorganic material that consists of at least two elementary spherical particles, each of said spherical particles comprising metal nanoparticles that are between 1 and 300 nm in size and a mesostructured matrix with an oxide base of at least one element X that is selected from the group that consists of aluminum, titanium, tungsten, zirconium, gallium, germanium, tin, antimony, lead, vanadium, iron, manganese, hafnium, niobium, tantalum, yttrium, cerium, gadolinium, europium and neodymium is described, whereby said matrix has a pore size of between 1.5 and 30 nm and has amorphous walls with a thickness of between 1 and 30 nm, said elementary spherical particles having a maximum diameter of 10 μm. Said material can also contain zeolitic nanocrystals that are trapped within said mesostructured matrix.

A phosphor including a main production phase of a phosphor expressed by a composition formula of MmAaBbOoNn:Zz (where an element M is one or more bivalent elements, an element A is one or more trivalent elements, an element B is one or more tetravalent elements, O is oxygen, N is nitrogen, an element Z is an activator, n=2 / 3m+a+4 / 3b−2 / 3o, m / (a+b)≧1 / 2, (o+n) / (a+b)>4 / 3, wherein m=a=b=1 and o and n is not 0). A phosphor including 24 wt % to 30 wt % of Ca (calcium), 17 wt % to 21 wt % of Al (aluminum), 18 wt % to 22 wt % of Si (silicon), 1 wt % to 15 wt % of oxygen, 15 wt % to 33 wt % of nitrogen and 0.01 wt % to 10 wt % of Eu (europium), wherein an emission maximum in an emission spectrum is in a range of 600 nm to 660 nm; and wherein color chromaticity x of light emission is in a range of 0.5 to 0.7, and color chromaticity y of the light emission is in a range of 0.3 to 0.5.

To provide a phosphor that stably shows high emission intensity and brightness as well as superior temperature characteristics, under excitation by near-ultraviolet light, the phosphor contains an alkaline-earth metal aluminate and has a crystal phase comprising an alkali metal element and, in that crystal phase, the rate of substituted Eu (europium) to the number of sites which can be substituted with Eu of the crystal phase is 25% or higher and the ratio of the alkali metal element to the number of sites which can be substituted with Eu of the crystal phase is 3% or lower.