Toyoda Gosei Co., Ltd.

Tridonic Optoelectronics Gmbh

Litec Gbr

Leuchstoffwerk Breitungen Gmbh

Other

Bundesdruckerei Gmbh

Leuchtstoffwerk Breitungen Gmbh

Fa. Leuchtstoffwerk Breitungen Gmbh

Tridonic Jennersdorf Gmbh

Wolfgang Kempfert

Detlef Starick

Peter Pachler

Stefan Tasch

Walter Tews

Gundula Roth

Koichi Ota

Atsuo Hirano

Akihito Ota

Manfred Paeschke

Wolfgang Schmidt

Oliver Muth

Benedikt Ahlers

Anett Bailleu

Paul Hartmann

Sylke Rösler

Hans Hoschopf

Sven Rösler

Christian Kunath

Cheng-Jun Duan

Guido Haussmann

Roland Heise

Rudolf Dennstedt

Arnim Franz-Burgholtz

Cornelia Vandahl

Gustav Martin Bartel

Guido HAUßMANN

The present invention relates to alkaline earth metal silicate luminophores having improved long-term stability and to a corresponding method for improving the long-term stability of alkaline earth metal silicate luminophores. The luminophore according to the invention is a luminophore comprising a base lattice according to the general chemical formula EASiO, where x, y, z&#x3e;0. The component EA is formed by one or more alkaline earth metals. An activator, for example Euor Mn, is doped into the base lattice. The luminophore has the fundamental property to absorb radiation in a first wavelength range and emit radiation in a second wavelength range that is different from the first wavelength range. The luminophore is designed in the form of crystals. According to the invention, the surfaces of the crystals of the luminophore are chemically modified such that at least portions of the surfaces thereof are formed by a chemical compound of the general formula EaZ. The component Z is formed by anions, which can be chemically combined with the EA cations of the luminophore. The variable u is equal to an ion charge of the anions Z. The chemical modification is therefore not a coating.

Alkaline earth metal silicate luminophores and method for improving the long term stability thereof

The invention relates to a light emitting device having a radiation emitting element, for example a light emitting diode, and a luminescent material which is able to absorb a part of the radiation sent out by the radiation emitting element and to send out light with a wavelength which is different from the wavelength of the absorbed radiation. The device further has diffusing particles which are able to scatter a part of the radiation sent out by the radiation emitting element, and/or to scatter a part of the light sent out by the luminescent material. The diffusing particles are of non-activated luminescent material, through which production is simplified.

Light emitting device with a non-activated luminescent material

The light emitting device has a light emitting diode which is made of a nitride semiconductor and a phosphor which absorbs a part of lights emitted from the light emitting diode and emits different lights with wavelengths other than those of the absorbed lights. The phosphor is made of alkaline earth metal silicate fluorescent material activated with europium.

Light emitting device

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)SiOaPObAlOcBOdGeO: y Euand/or (2-x-y)BaOx((Sr, Ca)O (1-a-b-c-d)SiOaPObAlOcBOdGeO: y Eu. 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)O:Eu or can contain alkaline-earth magnesium disilicate.

Light source with a light-emitting element

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)SiOaPObAlOcBOdGeO: y Euand/or (2-x-y)BaO x((Sr, Ca)O (1-a-b-c-d)SiOaPObAlOcBOdGeO: y Eu. 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)O:Eu or can contain alkaline-earth magnesium disilicate.

Light emitting device having a divalent-europium-activated alkaline earth metal orthosilicate phosphor

Light emitting device having phosphor of alkaline earth metal silicate

The present invention provides a secured document including a composition capable of anti-Stokes fluorescence containing an ion capable of absorption of electromagnetic radiation, an ion capable of emitting electromagnetic radiation, and a matrix composition comprising gadolinium, yttrium, lanthanum, and lutetium, wherein the wavelength of the emitted electromagnetic radiation is shorter than the wavelength of the absorbed electromagnetic radiation, and wherein the concentrations of the absorbing and emitting ions are adjusted to achieve concentration quenching of anti-Stokes luminescence.

Anti-stokes fluorescent compositions and methods of use

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)SiO aP O bAl O cB O dGeO :yEu and/or (2-x-y)BaOx((Sr, Ca)O(1-a-b-c-d)SiO aP O bAl O cB O dGeO :yEu . 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)O :Eu or can contain alkaline-earth magnesium disilicate.

Light source comprising a light-emitting element

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Bad Liebenstein, Germany

Wolfgang Kempfert