35results about How to "Short afterglow time" patented technology

The invention discloses a rare earth oxide solid solution ceramic scintillator and a preparation method thereof. The main component of the ceramic scintillator is Gd2xLu2yY2(1-x-y-z)Eu2zO3 (the x is more than or equal to 0.1 and less than or equal to 0.6, the y is more than or equal to 0.1 and is less than or equal to 0.4, and the z is more than or equal to 0.01 and less than or equal to 0.1), and the ceramic scintillator has a crystal structure with a cubic Ia3 point group. Ceramic powder can be synthesized by a chemical coprecipitation method. The coprecipitation method adopts ammonia, ammonium hydrogen carbonate or a mixed solution of the ammonium water and the ammonium hydrogen carbonate as a precipitating agent, titrates the precipitating agent into a solution of gadolinium nitrate, lutecium nitrate, yttrium nitrate and europium nitrate to obtain a precipitate, and then the precipitate is dried and calcined to obtain nano-powder. The obtained powder is pressed into a ceramic blank through an isostatic compaction method, then the pressureless sintering is performed in vacuum or hydrogen atmosphere, the sintering temperature is between 1,600 and 1,900 DEG C, transparent Gd2xLu2yY2(1-x-y-z)Eu2zO3 ceramic can be obtained, a ceramic product with the needed dimension is prepared after the cutting, grinding and polishing, and the transmission rate of the ceramic in a visible region (400-800 nanometers) is more than or equal to 65 percent. The ceramic scintillator emits red light with a main wavelength of 610 nanometers under the excitation of ultraviolet light or X rays, and can be used for scintillating materials of imaging and detection of medical and industrial X rays.

The invention provides vacuum ultraviolet induced green emitting phosphor which is characterized by having the following concrete chemical formula: M3 minus 2xBPO7: Tbx, Rx, wherein x is more than 0 and less than or equal to 0.3, R is one or several of Li, Na and K, and M is one or several of Mg, Zn, Ca, Sr and Ba. The invention also provides a method for preparing the green emitting phosphor, comprising the following steps: firstly, weighing corresponding raw materials according to the weight ratio expressed in the chemical formula; secondly, carrying out high-temperature roasting on the raw materials and rinsing coasted materials; and thirdly, carrying out separation, filtration, size grading and drying on the rinsed materials to obtain the vacuum ultraviolet induced green emitting phosphor having stable chemical property, short after time and excellent luminance.

The invention relates to zinc silicate manganese green emitting fluorescent powder and the manufacture method. It includes the following steps: adding SiO2 or silica slurry into zinc nitrate and urea water solution to make suspension, manganese sulfate solution, dropping excessive ammonia to generate precipitate; keeping temperature of precipitate in air or inert gas and gaining the fluorescent powder after processed. The feature is that the grain size is normally 1um, and has equally manganese ion distribution, and the keeping temperature declines about 200 degree centigrade. The invention has good emitting performance and persistent quality.

The invention relates to a warm white fluorescent powder excited by an ultraviolet LED. According to the fluorescent powder, InNbO4 serves as a host material, and the warm white fluorescent powder In1-x-y-zDyxTmyEuzNbO4 is obtained by simultaneously doping rare earth ions such as 0.01-0.05at.% of Dy3+, 0.01-0.05at.% of Tm+3+ and 0-0.03at.% of Eu3+ into the In3+ position, wherein x ranges from 0.01 to 0.05, y ranges from 0.01 to 0.05, and z ranges from 0 to 0.03. The rare-earth-doped niobate-based warm white fluorescent powder for the LED has the advantages of being simple in preparing process, high in light-emitting intensity, adjustable in color, capable of achieving a warm color, short in fall time, good in stability and the like, and can be widely applied to the LED field.

The invention discloses a red fluorescent powder for a PDP (Plasma Display Panel) and a preparation method thereof. The chemical formula of the red fluorescent powder is (Y1-x-y-zEuxREyRz)2O3, wherein x is not less than 0.005 and not more than 0.40, y is not less than 0.005 and not more than 0.40, z is not less than 0.005 and not more than 0.10, RE is rare-earth metal and R is alkali metal. The main light-emitting ion in the red fluorescent powder disclosed by the invention is Eu<3+>. Under the excitation of vacuum ultraviolet (VUV) light, after absorbing a certain amount of energy, the red fluorescent powder can transfer the energy to the Eu<3+>; the Eu<3+> produces red emission and an auxiliary ion R results in lattice distortion of the red fluorescent powder, so that the afterglow time of the Eu<3+> can be shortened effectively; moreover, the raw material for synthesis of the red fluorescent powder is non-toxic, the preparation process is simple and the industry production is easily realized.

The invention discloses a preparation method of zinc manganese silicate fluorescent powder with short afterglow. The fluorescent powder is prepared by a high temperature solid state method, wherein the source of Mn is ZnMn2O4 instead of conventional manganese oxide or manganese carbonate or other compounds. The zinc manganese silicate green fluorescent powder prepared by the method is high in luminous intensity and short in afterglow time, thus completely meeting the requirement on 3D plasma display. The preparation method does not change existing technology of preparing the zinc manganese silicate fluorescent powder by the high temperature solid state method, thus being easy to implement industrially, and very applicable to scale production.

The invention discloses a Cr < 3 + >-doped gallium aluminate near-infrared long-afterglow luminescent material and a preparation method thereof. The general chemical formula of the near-infrared long-afterglow luminescent material is Zn3GaxAl2-xGaeTibSn2-a-bO10: yCr < 3 + >. The preparation method comprises the following steps: weighing the raw materials according to the molar ratio of the substances in the equation, adding the fluxing agent, grinding in an agate mortar, and uniformly mixing to obtain a precursor; putting the precursor into an alumina crucible, and pre-sintering in an air or neutral atmosphere; and grinding and uniformly mixing a sample obtained by presintering, and calcining in air or neutral atmosphere to obtain the Cr < 3 + > gallium aluminate near-infrared long-afterglow luminescent material. The near-infrared long-afterglow fluorescent powder disclosed by the invention has the advantages of low raw material cost, simplicity and feasibility in operation, low requirements on equipment and the like. The long-afterglow luminescent material has the advantages that the emission range is located in a near-infrared region, and the long-afterglow luminescent material is long in afterglow time and the like.

The present invention relates to new material, and is especially new type of green photoluminescent phosphor and its preparation. The phosphor is RE Tb activated aluminate green phosphor in the expression of M1-XAl12O19:Tb3+x, where, M is Ba2+, Sr2+ and Ca2+, and x is 0.005-0.06. The phosphor is prepared through either a solid phase process including mixing and grinding materials terbium oxide, alumina, barium carbonate and boron oxide, and roasting for over 2 hr; or a sol-gel process including dissolving barium carbonate, aluminum nitrate a RE nitrate in citric acid solution, heating and stirring in water bath to form sol, drying the sol to form loose black powder, grinding and high temperature roasting. The phosphor has short afterglow, high light emitting strength, high light emitting efficiency, and small and homogeneous grain size.

The invention discloses rare earth borate-based red fluorescent powder. According to the fluorescent powder, CaInBO4 is used as a base body, 0.02-0.08 at.% of Al<3+> is doped to enter In<3+> bit, 0.02-0.08 at.% of Ba<2+> is doped to enter Ca<2+> bit and 0.07-0.10 at.% of Eu<3+> is doped to enter In<3+> bit, so that fluorescent powder (In(1-x-z), Alx, Euz)(Ca(1-y), Bay)BO4 is obtained, wherein x is equal to 0.02-0.04, y is equal to 0.05-0.07, and z is equal to 0.07-0.1. The rare earth borate-based red fluorescent powder provided by the invention has excellent properties of high luminous intensity, warm color, rapid decay, short persistence, good heat stability, easiness in long-term preservation and wide application range.

The invention relates to a low-pressure gas discharge lamp (10) for use in a scanning or blinking backlighting system, the low-pressure gas discharge lamp (10) comprising a luminescent layer (20) comprising a luminescent material selected from a group comprising: (Sr1-x-y-z, Bax, Cay, Eu(II)z)2Si04 (also known as XSO), (Sr1-x-y-z, Bax, Cay, Eu(II)z)Si2N2O2 (also known as XSON), and (Sr1-x-y-z, Bax, Cay, Eu(II)z)2Si5N8 (also known as XSN), wherein 0=x<1, 0=y<, 0<z=0.20, and x+y+z=l. The luminescent materials according to the invention have a relatively short decay time (less than 0.5 milliseconds), resulting in a relatively short afterglow time of the low-pressure gas discharge lamp (10) according to the invention. When using known low- pressure gas discharge lamps, for example, comprising the luminescent materials BAM, LAP and YOX in the scanning or blinking backlighting system, the afterglow time of these luminescent materials creates visible motion artifacts, especially when the scanning or blinking time is increased from 50 Hertz or 60 Hertz to, for example, 90 Hertz or 100 Hertz. Replacing the known luminescent materials LAP and/or YOX with luminescent material according to the invention will result in a reduction of the motion artifacts.

The invention relates to a boron aluminate luminescent material capable of generating green light and a preparation method thereof. The chemical formula of the luminescent material capable of generating green light is M1-x-y-zGdxTbyNzAl3BO7, wherein M is at least one of Ba, Sr, N is Na, Li or K, and x, y, and z satisfy the relations: 0.001 <= x <= 0.20, 0.005 <= y <= 0.50, 0.02 <= z <= 0.30, 1-x-y-z > 0. The preparation method comprises the steps: weighing raw materials and a flux in proportion; grinding and mixing well, then pre-sintering under a lower temperature; then calcining under a temperature of 900 to 1100 DEG C for 1 to 24 hours; grinding after cooling; and obtaining the boron aluminate luminescent material capable of generating green light of the invention. The method of the invention is simple, has no pollution, and is benefit for industrial production. The obtained luminescent material capable of generating green light has short afterglow, high luminous intensity and excellent luminous performance, and can be widely used for PDP or mercury-free fluorescent lamp.