Phosphors include a CaAlSiN.sub.3 family crystal phase, wherein the CaAlSiN.sub.3 family crystal phase comprises at least one element selected from the group consisting of Mn, Ce, Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, and Yb.

Embodiments of the invention include a wavelength-converting material defined by AE.sub.3x1y+zRE.sub.3x2+yz[Si.sub.9wAl.sub.w(N.sub.1yC.sub.y).sup.[4](N.sub.16zwO.sub.z+w).sup.[2]]:Eu.sub.x1,Ce.sub.x2, where AE=Ca, Sr, Ba; RE=Y, Lu, La, Sc; 0x10.18; 0x20.2; x1+x2>0; 0y1; 0z3; 0w3.

The present invention relates to a novel method for preparing a water-insoluble metal hydroxide, and a use thereof. The water-insoluble metal hydroxide of the present invention is conveniently and efficiently prepared s through the high-temperature heat treatment step two times and the washing step, and thus contains a small amount of an alkali metal and has a high crystallinity and a phase purity. The water-insoluble metal hydroxide of the present invention or metal oxide therefrom exhibits an absorption wavelength at a low wavelength range (for example, 490 nm or less) and a light emitting wavelength at a high wavelength range (for example, from 500 nm or more to less than 1,100 nm). Accordingly, the water-insoluble metal hydroxide of the present invention may be efficiently used in various applications such as a fire retardant, an antacid, an adsorbent and so forth, and may also be doped with another metal ion to be utilized as a raw material for fabricating a catalyst, a fluorescent material, an electrode material, a secondary battery material and the like.

A halide material, such as scintillator crystals of LaBr.sub.3:Ce and SrI.sub.2:Eu, with a passivation surface layer is disclosed. The surface layer comprises one or more halides of lower water solubility than the scintillator crystal that the surface layer covers. A method for making such a material is also disclosed. In certain aspects of the disclosure, a passivation layer is formed on a surface of a halide material such as a scintillator crystal of LaBr.sub.3:Ce of SrI.sub.2:Eu by fluorinating the surface with a fluorinating agent, such as F.sub.2 for LaBr.sub.3:Ce and HF for SrI.sub.2:Eu.

Phosphors include a CaAlSiN.sub.3 family crystal phase, wherein the CaAlSiN.sub.3 family crystal phase comprises at least one element selected from the group consisting of Mn, Ce, Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, and Yb.

Embodiments of the invention include a wavelength-converting material defined by AE.sub.3x1y+zRE.sub.3x2+yz[Si.sub.9wAl.sub.w(N.sub.1yC.sub.y).sup.[4](N.sub.16zwO.sub.z+w).sup.[2]]:Eu.sub.x1,Ce.sub.x2, where AE=Ca, Sr, Ba; RE=Y, Lu, La, Sc; 0x10.18; 0x20.2; x1+x2>0; 0y1; 0z3; 0w3.

Embodiments of the invention include a wavelength-converting material defined by AE.sub.3x1y+zRE.sub.3x2+yz[Si.sub.9wAl.sub.w(N.sub.1yC.sub.y).sup.[4](N.sub.16zwO.sub.z+w).sup.[2]]Eu.sub.x1,Ce.sub.x2, where AE=Ca, Sr, Ba; RE=Y, Lu, La, Sc; 0x10.18; 0x20.2; x1+x2>0; 0y1; 0z3; 0w3.

A phosphor having a formula of T.sub.xE.sub.ySi.sub.zN.sub.rTb.sub.aL.sub.bM.sub.c is provided, in which T is Mg, Ca, Sr or Ba; E is Mg, Ca, Ba, Ti, Cu, Zn, B, Al, In, Sn, Sb, Bi, Ga, Y, La or Lu; L is Li, Na or K; M is Ce, Pr, Nd, Pm, Sm, Gd, Dy, Ho, Er, Tm, Yb or Mn; and 1.4x2.6, 0y0.5, 4.3z5.6, 7.4r9, 0.01a0.5, 0b0.5, 0c0.5, in which Tb ion is used as a luminescence center, and valence of the Tb ion is lower than 3+, and the phosphor is excited by an excitation light and has an emission band with a full width at half maximum greater than 50 nm. A method of forming the phosphor is also provided.

An improved system and method for reading an upconversion response from nanoparticle inks is provided. A is adapted to direct a near-infrared excitation wavelength at a readable indicia, resulting in a near-infrared emission wavelength created by the upconverting nanoparticle inks. A short pass filter may filter the near-infrared excitation wavelength. A camera is in operable communication with the short pass filter and receives the near-infrared emission wavelength of the readable indicia. The system may further include an integrated circuit adapted to receive the near-infrared emission wavelength from the camera and generate a corresponding signal. A readable application may be in operable communication with the integrated circuit. The readable application receives the corresponding signal, manipulates the signal, decodes the signal into an output, and displays and/or stores the output.

Phosphors include a CaAlSiN.sub.3 family crystal phase, wherein the CaAlSiN.sub.3 family crystal phase comprises at least one element selected from the group consisting of Mn, Ce, Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, and Yb.