A phosphor plate including: a complex containing an α-sialon phosphor and a sintered body containing spinel represented by a general formula M.sub.2xAl.sub.4-4xO.sub.6-4x (where M represents at least one of Mg, Mn, and Zn, and 0.2<x<0.6). In addition, there is provided a light emitting device including: a group III nitride semiconductor light emitting element; and the phosphor plate provided on one surface of the group III nitride semiconductor light emitting element. Further, there is provided a method for manufacturing the phosphor plate.

An image detector for a radiation-based imaging technique is disclosed. The image detector may comprise a detector material on a substrate. The detector material may be an optically active material represented by the following formula (I) (M′).sub.8 (M″M′″).sub.6O.sub.24(X,X′).sub.2:M″″ Further is disclosed the use of the image detector and the use of the optically active material represented by the formula (I).

Embodiments of the invention include a semiconductor light emitting device for emitting a first light at a first wavelength and a wavelength conversion medium arranged to convert at least part of the first light into a second light at a second wavelength. The wavelength conversion medium is disposed between a periodic antenna array and the semiconductor light emitting device. The periodic antenna array includes a plurality of antennas. The periodic antenna array supports surface lattice resonances arising from diffractive coupling of localized surface plasmon resonances in at least one of the antennas.

A method of increasing the luminescence efficiency of titanium-doped oxide crystal, used as a laser material, is disclosed. This is accomplished by tempering the crystal at a temperature from 1750° C. to 50° C. below the melting point of the oxide crystal in a hydrogen protecting atmosphere with a constant partial pressure of the aluminium suboxide Al.sub.2O gas. By applying the method of the present invention, its luminescence efficiency of titanium-doped oxide crystal increases by 10 to 50 percent, and possibly by as much as 100 percent or more compared to previous technological treatments.

The object of the present invention is to provide an oxide-based phosphor comprising elements other than rare earth elements as light-emitting elements, with low material costs, while achieving high luminous efficacy. The means for achieving the object is a phosphor comprising the following (1) to (3): (1) zirconium oxide, (2) titanium, and (3) at least one element selected from the group consisting of phosphorus, selenium, boron, and silicon.

A lighting device for adjusting the color temperature of white light emitted by a luminescent material is disclosed. The lighting device comprises: a luminescent material configured to emit white light when being exposed to electromagnetic radiation of a preselected wavelength range; at least one excitation unit configured to expose the luminescent material to electromagnetic radiation of a first wavelength range selected from the range of 230-330 nm; at least one excitation unit configured to expose the luminescent material to electromagnetic radiation of a second wavelength range, different from the first wavelength range, selected from the range of 300-600 nm; a metering unit configured to adjust the ratio of the irradiances of electromagnetic radiation of first wavelength range and of electromagnetic radiation of second wavelength range that is exposed on the luminescent material.

A lighting device for adjusting the color temperature of white light emitted by a luminescent material is disclosed. The lighting device comprises: a luminescent material configured to emit white light when being exposed to electromagnetic radiation of a preselected wavelength range; at least one excitation unit configured to expose the luminescent material to electromagnetic radiation of a first wavelength range selected from the range of 230-330 nm; at least one excitation unit configured to expose the luminescent material to electromagnetic radiation of a second wavelength range, different from the first wavelength range, selected from the range of 300-600 nm; a metering unit configured to adjust the ratio of the irradiances of electromagnetic radiation of first wavelength range and of electromagnetic radiation of second wavelength range that is exposed on the luminescent material.

The invention relates to a material represented by the following formula (I)
(M′).sub.8(M″M′″).sub.6O.sub.24(X,X′).sub.2:M″″   formula (I).
Further, the invention relates to a luminescent material, and to different medical imaging and diagnostic methods of using the material. Also disclosed is a method of securely identifying an item using the material.

Synthesizing a color stable Mn.sup.4+ doped phosphor by contacting a gaseous fluorine-containing oxidizing agent with a precursor of: A.sub.aB.sub.bC.sub.cD.sub.dX.sub.x:Mn.sup.4+; A.sub.aiB.sub.biC.sub.ciD.sub.dX.sub.xY.sub.d:Mn.sup.4+; A.sup.1.sub.3G.sub.2mnMn.sub.mMg.sub.nLi.sub.3F.sub.12O.sub.p; or AZF.sub.4:Mn.sup.4+. Where A is Li, Na, K, Rb, Cs, or a combination; B is Be, Mg, Ca, Sr, Ba, or a combination; C is Sc, Y, B, Al, Ga, In, Tl, or a combination; D is Ti, Zr, Hf, Rf, Si, Ge, Sn, Pb, or a combination; X is F or a combination of F and one of Br, Cl, and I; Y is O, or a combination of O and one of S and Se; A.sup.1 is Na or K, or a combination; G is Al, B, Sc, Fe, Cr, Ti, In, or a combination; Z is La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Sc, Y, In, or a combination.

A material represented by the following formula (I)
(M).sub.8M.sub.6M.sub.6O.sub.24(X,S).sub.2:Mformula (I).
Also disclosed is an ultraviolet radiation sensing material, an X-radiation sensing material, a device and a method for determining the intensity of ultraviolet radiation.