A method for producing a fluoride fluorescent material comprises: preparing fluoride particles having a composition containing at least one element or ion A selected from the group consisting of alkaline metal elements and NH.sub.4.sup.+, at least one element M selected from the group consisting of Group-4 elements and Group-14 elements, Mn.sup.4+, and F, in which a molar ratio of A in 1 mol of the composition is 2, a total molar ratio of M and Mn.sup.4+ is 1, a molar ratio of Mn.sup.4+ is in a range of more than 0 and less than 0.2, and a molar ratio of F is 6; subjecting the fluoride particles to a first heat treatment at a temperature of 500° C. or more in an inert gas atmosphere; washing the first heat-treated fluoride particles with a washing liquid; and bringing the washed fluoride particles into contact with a fluorine-containing substance and subjecting the resulting fluoride particles to a second heat treatment at a temperature of 400° C. or more.

To provide a semiconductor light emitting device which is capable of accomplishing a broad color reproducibility for an entire image without losing brightness of the entire image. A light source provided on a backlight for a color image display device has a semiconductor light emitting device comprising a solid light emitting device to emit light in a blue or deep blue region or in an ultraviolet region and phosphors, in combination. The phosphors comprise a green emitting phosphor and a red emitting phosphor. The green emitting phosphor and the red emitting phosphor are ones, of which the rate of change of the emission peak intensity at 100° C. to the emission intensity at 25° C., when the wavelength of the excitation light is 400 nm or 455 nm, is at most 40%.

A potassium hexafluoromanganate is represented by General Formula: K.sub.2MnF.sub.6, and a diffuse reflectance with respect to light having a wavelength of 550 nm is 60% or more.

A fiber optic plate 122 including a plurality of core glasses 122a, a clad glass 122b covering the core glass 122a, and a light-absorbing glass 122c disposed between the plurality of core glasses 122a, wherein a content of TiO.sub.2 in the core glass 122a is 7% by mass or less, a content of B.sub.2O.sub.3 in the core glass 122a is 15% by mass or more, and a content of WO.sub.3 in the core glass 122a is more than 0% by mass.

A method of forming a perovskite thin film and a light-emitting device including a layer manufactured by the method.

Eutectic lithium chloride-cerium chloride (LiCl—CeCl.sub.3) compositions are described. An exemplary eutectic composition has about 75 mole % LiCl and about 25 mole % CeCl.sub.3. The eutectic compositions can have optical and/or scintillation properties. Also described are methods of preparing the eutectic compositions as well as methods of using radiation detectors including the eutectic compositions in the detection of radiation, including thermal neutrons.

A light emitting device includes a Chip Scale Packaged (CSP) LED, the CSP LED including an LED chip that generates blue excitation light; and a photoluminescence layer that covers a light emitting face of the LED chip, wherein the photoluminescence layer comprises from 75 wt % to 100 wt % of a manganese-activated fluoride photoluminescence material of the total photoluminescence material content of the layer. The device/CSP LED can further include a further photoluminescence layer that covers the first photoluminescence and that includes a photoluminescence material that generates light with a peak emission wavelength from 500 nm to 650 nm.

Green-emitting phosphors are useful in devices including an LED light source radiationally coupled and/or optically coupled to the phosphors, which are selected from [Ba.sub.1−a−bSr.sub.aCa.sub.b].sub.x[Mg,Zn].sub.y(UO.sub.2).sub.z([P,V]O.sub.4).sub.2(x+y+z)/3, where 0≤a≤1, 0≤b≤1, 0.75≤x≤1.25, 0.75≤y≤1.25, 0.75≤z≤1.25; and [Ba,Sr,Ca,Mg,Zn].sub.p(UO.sub.2).sub.q[P,V].sub.rO.sub.(2p+2q+5r)/2, where 2.5≤p≤3.5, 1.75≤q≤2.25, 3.5≤r≤4.5.

A method for producing a fluoride fluorescent material comprises: preparing fluoride particles having a composition containing at least one element or ion A selected from the group consisting of alkaline metal elements and NH.sub.4.sup.+, at least one element M selected from the group consisting of Group-4 elements and Group-14 elements, Mn.sup.4+, and F, in which a molar ratio of A in 1 mol of the composition is 2, a total molar ratio of M and Mn.sup.4+ is 1, a molar ratio of Mn.sup.4+ is in a range of more than 0 and less than 0.2, and a molar ratio of F is 6; subjecting the fluoride particles to a first heat treatment at a temperature of 500° C. or more in an inert gas atmosphere; washing the first heat-treated fluoride particles with a washing liquid; and bringing the washed fluoride particles into contact with a fluorine-containing substance and subjecting the resulting fluoride particles to a second heat treatment at a temperature of 400° C. or more.

Provided is a method for producing an inorganic fluoride luminescent material using a non-aqueous solution.

The method for producing an inorganic fluoride luminescent material includes: either preparing a first non-aqueous solution that contains a first ion, a second ion, and a first non-aqueous hydrogen fluoride-containing liquid, and a second non-aqueous solution that contains a third ion and a second non-aqueous hydrogen fluoride-containing liquid, or preparing a third non-aqueous solution that contains a first ion, a second ion, a third ion, and a third non-aqueous hydrogen fluoride-containing liquid; and either mixing the first non-aqueous solution and the second non-aqueous solution with a non-aqueous organic liquid, or mixing the third non-aqueous solution with a non-aqueous organic liquid, to obtain an inorganic fluoride luminescent material containing a first element M1 and/or ammonium, a second element M2, and a third element M3.