The wavelength converter includes a support, and a wavelength conversion layer disposed on the support. The wavelength conversion layer contains a fluorescent layer containing a fluorescent material with a composition represented by formula (1) below, and having a thickness of from 5 μm to 155 μm. A ratio of a sum of cross-sectional areas of particles of the fluorescent material in a cross-section of the wavelength conversion layer orthogonal to a disposed surface of the wavelength conversion layer that is disposed on the support and including a full width of the wavelength conversion layer to a cross-sectional area of the cross-section of the wavelength conversion layer is from 5% to 40%. In the formula (1), M.sup.1 is at least one selected from the rare earth elements other than La and Ce; a total amount of yttrium (Y), gadolinium (Gd), and lutetium (Lu) by mole with respect to a total amount of M.sup.1 by mole is 90% or more; and p, q, r, and s satisfy 2.7≤p+q+r≤3.3, 0≤r≤1.2, 10≤s≤12, and 0<q≤1.2.

La.sub.pCe.sub.qM.sup.1.sub.rSi.sub.6N.sub.s  (1)

Provided are a method for producing a ceramic composite material that has a high light emission intensity, a ceramic composite material, and a light emitting device. The method for producing a ceramic composite material, includes: preparing a green body containing a nitride fluorescent material having a composition represented by the following chemical formula (I) and aluminum oxide particles mixed with each other; and performing primary sintering the green body at a temperature in a range of 1,250° C. or more and 1,600° C. or less to provide a first sintered body:
M.sub.wLn.sup.1.sub.xA.sub.yN.sub.z  (I)
wherein in the chemical formula (I), M represents at least one element selected from the group consisting of Ce and Pr; Ln.sup.1 represents at least one element selected from the group consisting of Sc, Y, La, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu; A represents at least one element selected from the group consisting of Si and B; and w, x, y, and z each satisfy 0<w≤1.0, 2.5≤x≤3.5, 5.5≤y≤6.5, and 10≤z≤12.

Provided is a wavelength conversion member that is less decreased in luminescence intensity with time by irradiation with light of an LED or LD and a light emitting device using the wavelength conversion member. A wavelength conversion member is formed of an inorganic phosphor dispersed in a glass matrix, wherein the glass matrix contains, in % by mole, 30 to 85% SiO.sub.2, 0 to 20% B.sub.2O.sub.3, 0 to 25% Al.sub.2O.sub.3, 0 to 3% Li.sub.2O, 0 to 3% Na.sub.2O, 0 to 3% K.sub.2O, 0 to 3% Li.sub.2O+Na.sub.2O+K.sub.2O, 0 to 35% MgO, 0 to 35% CaO, 0 to 35% SrO, 0 to 35% BaO, 0.1 to 45% MgO+CaO+SrO+BaO, and 0 to 4% ZnO, and the inorganic phosphor is at least one selected from the group consisting of an oxide phosphor, a nitride phosphor, an oxynitride phosphor, a chloride phosphor, an oxychloride phosphor, a halide phosphor, an aluminate phosphor, and a halophosphate phosphor.

Phosphor, a preparation method for the phosphor, and a light emitting device having the phosphor. The phosphor comprises an inorganic compound which at least comprises an element M, an element A, an element D, and an element R; the element M is one or two elements selected from the group consisting of Lu, La, Pr, Nd, Sm, Y, Tb, and Gd and must comprise Lu; the element A is Si and/or Ge; the element D is one or two elements selected from the group consisting of O, N, and F and must comprise N; the element R is Ce and/or Dy. Since the ionic radius of Lu3+ is smaller than that of La3+, when the inorganic compound comprises element Lu, the original ligand site would be contracted. In order to reduce lattice distortion due to the ligand site contraction, the adjacent ligand site expands, and the photochromic property is adjusted.

Embodiments of the invention include a wavelength-converting composition as defined by R.sub.3-x-y-zA.sub.x+yM.sub.zSi.sub.6-w1Al.sub.w1O.sub.3x+y+w1N.sub.11-7x/3-y-w1□2-2x/3, with □ being vacancies of the structure that are filled by oxygen atoms with 0<x≤3, −3≤y<3, 0<z<1,0≤w1≤6, 0≤x+y, x+y+z≤3, 11−7/3x−y−w1≤0, and 3x+y+w1≤13. R is selected from the group comprising trivalent La, Gd, Tb, Y, Lu; A is selected from the group comprising bivalent Ca, Mg, Sr, Ba, and Eu; and M is selected from the group comprising trivalent Ce, Pr and Sm.

Provided is a wavelength conversion member that is less decreased in luminescence intensity with time by irradiation with light of an LED or LD and a light emitting device using the wavelength conversion member. A wavelength conversion member is formed of an inorganic phosphor dispersed in a glass matrix, wherein the glass matrix contains, in % by mole, 30 to 85% SiO.sub.2, 0 to 20% B.sub.2O.sub.3, 0 to 25% Al.sub.2O.sub.3, 0 to 3% Li.sub.2O, 0 to 3% Na.sub.2O, 0 to 3% K.sub.2O, 0 to 3% Li.sub.2O+Na.sub.2O+K.sub.2O, 0 to 35% MgO, 0 to 35% CaO, 0 to 35% SrO, 0 to 35% BaO, 0.1 to 45% MgO+CaO+SrO+BaO, and 0 to 4% ZnO, and the inorganic phosphor is at least one selected from the group consisting of an oxide phosphor, a nitride phosphor, an oxynitride phosphor, a chloride phosphor, an oxychloride phosphor, a halide phosphor, an aluminate phosphor, and a halophosphate phosphor.

The disclosure provides an LED white light device, including a blue light chip and phosphors. The blue light chip has a band of (455-470) nm. The phosphors include a dual-band yellow phosphor and a red phosphor having an excited light peak wavelength range of (610-660) nm. The yellow phosphor and the red phosphor are mixed according to a proportion of 1:(0.03-0.2) and cover the blue light chip, such that blue light emitted by the packaged LED white light device has a peak wavelength range of (450-465) nm. The disclosure also provides a preparation method of an LED white light device and an LED backlight module adopting the above LED white light device. The disclosure achieves the effects of blue light prevention, high color gamut and pure white simultaneously, the color uniformity and consistency are good, and a blue-green-red three-color continuous spectrum is provided, which is closer to a solar spectrum.

An embodiment relates to a phosphor composition, a light-emitting device package comprising the same, and a lighting apparatus and, more particularly, to a phosphor composition comprising a first phosphor, excited by an excitation light source, for emitting a first wavelength range of light, a second phosphor, excited by the excitation light source, for emitting a second wavelength range of light, and a third phosphor, excited by the excitation light source, for emitting a third wavelength range of light. The light emitted from the phosphor composition exhibits an increased intensity of light in a blue-green wavelength region with the consequent improvement of color rendering index and a shortened wavelength of light in a red wavelength region with the consequent improvement of luminous flux.

A sintered phosphor-composite having a high internal quantum efficiency and a high transmittance is provided. The object can be achieved with a sintered phosphor-composite including a nitride phosphor and a fluoride inorganic binder, wherein, in cross-sectional observation, the sintered phosphor-composite includes at least a portion in which voids of not more than 1 μm are present in a number of not more than 700 within a cross-sectional area of 0.046 mm.sup.2, or a portion having a void area fraction of not more than 3% within a cross-sectional area of 0.046 mm.sup.2.

A fluorescent material is provided that has improved luminance and can generate fluorescence by excitation light in wider wavelength range. A fluorescent material represented by a general formula La.sub.xCe.sub.ySi.sub.6N.sub.8+x+y, wherein 2.0x3.5, 0<y1.0, wherein the fluorescent material comprises 10 to 10000 ppm of Ba and/or Sr, and wherein a first wavelength and a second wavelength at which excitation intensities are 70% of the maximum of the excitation intensities are present in a wavelength range of 400 to 510 nm, the second wavelength being longer than the first wavelength, and a difference between the first wavelength and the second wavelength being 70 nm or more.