Provided is a method for producing a phosphor having a s chemical composition represented by formula (I), A.sub.2MF.sub.6:Mn (I) (A is one type or more of an alkali metal selected from Li, Na, K, Rb, and Cs, and includes at least Na and/or K, and M is one type or more of a tetravalent element selected from Si, Ti, Zr, Hf, Ge, and Sn.), the method comprising preparing a first hydrofluoric acid solution containing M and a second hydrofluoric acid solution containing A as well as either dissolving a compound containing Mn in either the first hydrofluoric acid solution or the second hydrofluoric acid solution or preparing a separate solution in which the compound containing Mn is dissolved. When the solutions are mixed to precipitate the phosphor of the formula (I), the solutions are mixed so that the concentration of M is 0.1 to 0.5 mol/liter when all the solutions are mixed. According to the present invention, a complex fluoride phosphor having excellent luminescence properties can be produced stably with high yield.

An embodiment of an LED lamp that generates light of a color temperature that decreases with decreasing power applied to the LED lamp may include at least one lighting arrangement that may include a first LED array of serially connected first LED chips, a second LED array of serially connected second LED chips; a first photoluminescence layer covering the first LED array for generating light of a first color temperature; a second photoluminescence layer covering the second LED array for generating light of a second different color temperature; and a linear resistor serially connected to the first LED array, wherein the first LED array and second LED array are connected in parallel.

A scintillation device including a support that includes microchannels and a composite of a metal halide scintillator with a solid polymeric matrix in the microchannels, wherein the solid polymeric matrix is transparent to electromagnetic radiation emitted by the metal halide scintillator; also included are methods of producing and using the scintillation device.

The present application discloses an anti-deterioration red phosphor, and a preparation method and an application thereof, and relates to the field of phosphor materials technology. The anti-deterioration red phosphor of the present application comprises a core-shell structure, the core-shell structure comprises an inner core and an outer shell, the inner core and the outer shell are independently selected from substances shown in a chemical formula I, and the chemical formula I is A.sub.2M.sub.(1-x)F.sub.6:xMn.sup.4+. The present application enhances the moisture resistance and anti-deterioration resistance of the phosphor by controlling the atom percentage of Mn.sup.4+ to be the lowest in the innermost layer of the inner core and the highest in the outermost layer of the inner core. Additionally, by incorporating an outer shell with minimal or even no Mn.sup.4+ content to encapsulate the inner core of the phosphor, it helps maintain a higher luminescent efficiency in coordination with the inner core.

A light emitting device for generating light of a color temperature that decreases with decreasing power applied to the light emitting device, the light emitting device comprising: a substrate; a first LED array of serially connected first LED chips on the substrate, a second LED array of serially connected second LED chips on the substrate, a first photoluminescence layer covering the first LED array for generating light of a first color temperature, a second photoluminescence layer covering the second LED array for generating light of a second different color temperature, and a linear resistor serially connected to the first LED array; wherein the first LED array and serially connected linear resistor, and second LED array are connected in parallel.