Abstract: The invention provides a method for producing a glass ceramic comprising the steps of melting a starting glass that is free from alkali, except for incidental contamination, and that contains at least one garnet-forming agent and at least one oxide of a lanthanoid; grinding the starting glass to produce a glass frit; molding by pressing and sintering the glass frit until at least one garnet phase containing lanthanoids is formed. A glass ceramic produced in this way may contain 5-50% by weight of SiO2, 5-50% by weight of Al2O3 and 10-80% by weight of at least one oxide selected from the group formed by Y2O3, Lu2O3, Sc2O3, Gd2O3, Yb2O3, Ce2O3, as well as 0.1-30% by weight of at least one oxide selected from the group formed by B2O3, Th2O3, and oxides of the lanthanoids, except Lu2O3, Gd2O3, Yb2O3, Ce2O3. Such a glass ceramic is suited especially for down conversion of excitation radiation in the blue and in the UV region of the spectrum.

Abstract: The invention proposes a method for producing glass ceramics which is particularly well suited as light conversion material, especially for down conversion. One initially produces a starting glass, containing (on an oxide basis) 5-50% by weight of SiO2, 5-50% by weight of Al2O3 and 10-80% by weight of at least one oxide selected from the from the group formed by Y2O3, Lu2O3, Sc2O3, Gd2O3, Yb2O3, Ce2O3, as well as 0.1-30% by weight of at least one oxide selected from the group formed by B2O3, Th2O3, and oxides of the lanthanoids, except Lu2O3, Gd2O3, Yb2O3, Ce2O3. Thereafter, the material is heated up for ceramization at a heating rate of at least 100 K/min to a temperature in the range of between 1000° C. to 1400° C. until crystallites are formed that contain a garnet phase. Thereafter, the material is cooled down to room temperature. Alternatively, controlled cooling-down from the molten state is possible.

Abstract: The invention provides a method for producing a glass ceramic comprising the steps of melting a starting glass that is free from alkali, except for incidental contamination, and that contains at least one garnet-forming agent and at least one oxide of a lanthanoid; grinding the starting glass to produce a glass frit; molding by pressing and sintering the glass frit until at least one garnet phase containing lanthanoids is formed. A glass ceramic produced in this way may contain 5-50 % by weight of SiO2, 5-50 % by weight of Al2O3 and 10-80 % by weight of at least one oxide selected from the group formed by Y2O3, Lu2O3, Sc2O3, Gd2O3, Yb2O3, Ce2O3, as well as 0.1-30% by weight of at least one oxide selected from the group formed by B2O3, Th2O3, and oxides of the lanthanoids, except Lu2O3, Gd2O3, Yb2O3, Ce2O3. Such a glass ceramic is suited especially for down conversion of excitation radiation in the blue and in the UV region of the spectrum.

Abstract: The invention provides a method for producing a glass ceramic comprising the steps of melting a starting glass that is free from alkali, except for incidental contamination, and that contains at least one garnet-forming agent and at least one oxide of a lanthanoid; grinding the starting glass to produce a glass frit; molding by pressing and sintering the glass frit until at least one garnet phase containing lanthanoids is formed. A glass ceramic produced in this way may contain 5-50% by weight of SiO2, 5-50% by weight of Al2O3 and 10-80% by weight of at least one oxide selected from the group formed by Y2O3, Lu2O3, Sc2O3, Gd2O3, Yb2O3, Ce2O3, as well as 0.1-30% by weight of at least one oxide selected from the group formed by B2O3, Th2O3, and oxides of the lanthanoids, except Lu2O3, Gd2O3, Yb2O3, Ce2O3. Such a glass ceramic is suited especially for down conversion of excitation radiation in the blue and in the UV region of the spectrum.

Abstract: A glass powder or a glass-ceramic powder is provided that includes multicomponent glasses with at least three elements, where the glass powder or a glass-ceramic powder has a mean particle size of less than 1 ?m. In some embodiments, the mean particle size is less than 0.1 ?m, while in other embodiments the mean particle size is less than 10 nm.

Abstract: The invention proposes a method for producing glass ceramics which is particularly well suited as light conversion material, especially for down conversion. One initially produces a starting glass, containing (on an oxide basis) 5-50% by weight of SiO2, 5-50 % by weight of Al2O3 and 10-80% by weight of at least one oxide selected from the from the group formed by Y2O3, Lu2O3, Sc2O3, Gd2O3, Yb2O3, Ce2O3, as well as 0.1-30% by weight of at least one oxide selected from the group formed by B2O3, Th2O3, and oxides of the lanthanoids, except Lu2O3, Gd2O3, Yb2O3, Ce2O3. Thereafter, the material is heated up for ceramization at a heating rate of at least 100 K/min to a temperature in the range of between 1000° C. to 1400° C. until crystallites are formed that contain a garnet phase. Thereafter, the material is cooled down to room temperature. Alternatively, controlled cooling-down from the molten state is possible.

Abstract: A glass powder or a glass-ceramic powder is provided that includes multicomponent glasses with at least three elements, where the glass powder or a glass-ceramic powder has a mean particle size of less than 1 ?m. In some embodiments, the mean particle size is less than 0.1 ?m, while in other embodiments the mean particle size is less than 10 nm.

Abstract: The invention provides a method for producing a glass ceramic comprising the steps of melting a starting glass that is free from alkali, except for incidental contamination, and that contains at least one garnet-forming agent and at least one oxide of a lanthanoid; grinding the starting glass to produce a glass frit; molding by pressing and sintering the glass frit until at least one garnet phase containing lanthanoids is formed. A glass ceramic produced in this way may contain 5-50 % by weight of SiO2, 5-50 % by weight of Al2O3 and 10-80 % by weight of at least one oxide selected from the group formed by Y2O3, Lu2O3, Sc2O3, Gd2O3, Yb2O3, Ce2O3, as well least one oxide selected from the group formed by B2O3, Th2O3, and oxides of the lanthanoids, except Lu2O3, Gd2O3, Yb2O3, Ce2O3. Such a glass ceramic is suited especially for down conversion of excitation radiation in the blue and in the UV region of the spectrum.

Abstract: The invention describes a solid-state light source comprising a solid-state emitter designed for emitting light energy, which preferably has an LED, a luminescent light conversion medium, made from glass or glass ceramics, for converting emitted light energy to light energy of a different frequency spectrum, and a coupling medium for decoupling the light energy to an ambient medium, such as air, the light conversion medium having a refractive index ncs, selected as a function of the refractive index nHL of the solid-state emitter in the range of 0.7·(nHL2)1/3 to 1.3·(nHL2)1/3.