Abstract: A light emitting device according to one embodiment includes: a board; plural first light emitting units each including a first light emitting element and a first fluorescent layer formed on the first light emitting element having a green phosphor; plural second light emitting units each including a second light emitting element and a second fluorescent layer formed on the second light emitting element having a red phosphor; the second fluorescent layers and the first fluorescent layers being separated in a non-contact manner with gas interposed there between; and plural third light emitting units each including a third light emitting element and a resin layer formed on the third light emitting element having neither a green phosphor nor the red phosphor, the third light emitting units being disposed between the first light emitting units and the second light emitting units.

Abstract: The fluorescent substance according to the embodiment is generally represented by (M1?xECx)aSibAlOcNd, and is a kind of the Sr2Si7Al3ON13 phosphors. The substance is in the form of crystals having a mean grain size of 20 to 100 ?m, and the aspect ratio thereof is in the range of 2 to 4. This substance emits luminescence having a peak in the wavelength range of 580 to 660 nm when excited by light of 250 to 500 nm. The embodiment also provides a light-emitting device comprising this substance in combination with a light-emitting element and a green light-emitting fluorescent substance.

Abstract: A light emitting device according to one embodiment includes a light emitting element that emits light having a wavelength of 380 nm to 470 nm; a CASN first red phosphor that is disposed on the light emitting element; a sialon second red phosphor that is disposed on the light emitting element; and a sialon green phosphor that is disposed on the light emitting element.

Abstract: A light emitting device according to one embodiment includes a board; plural first light emitting elements mounted on the board to emit light having a wavelength of 250 nm to 500 nm; plural second light emitting elements mounted on the board to emit light having a wavelength of 250 nm to 500 nm; a first fluorescent layer formed on each of the first light emitting elements, the first fluorescent layer including a first phosphor; and a second fluorescent layer formed on each of the second light emitting elements, the second fluorescent layer including a second phosphor. The second phosphor is higher than the first phosphor in luminous efficiency at 50° C., and is lower than the first phosphor in the luminous efficiency at 150° C.

Abstract: The embodiment provides a process for production of an oxynitride fluorescent substance. In the process, a compound represented by the formula: (Sr,Eu)2Si5N8, silicon nitride and aluminum nitride are mixed and then fired in a nitrogen atmosphere under high pressure.

Abstract: A light emitting device according to one embodiment includes a light emitting element that emits light having a wavelength of 250 nm to 500 nm and a fluorescent layer that is disposed on the light emitting element. The fluorescent layer includes a phosphor having a composition expressed by the following equation (1) and an average particle diameter of 12 ?m or more. (M1?x1Eux1)3?ySi13?zAl3+zO2+uN21?w??(1) (In the equation (1), M is an element that is selected from IA group elements, IIA group elements, IIIA group elements, IIIB group elements except Al, rare-earth elements, and IVB group elements. x1, y, z, u, and w satisfy the following relationship. 0<x1<1, ?0.1<y<0.3, ?3<z?1, ?3<u?w?1.

Abstract: A light emitting device according to one embodiment includes a light emitting element that emits light having a wavelength of 250 nm to 500 nm and a fluorescent layer that is disposed on the light emitting element. The fluorescent layer includes a phosphor having a composition expressed by the following equation (1) and an average particle diameter of 12 ?m or more. (M1?x1Eux1)3?ySi13?zAl3+zO2+uN21?w??(1) (In the equation (1), M is an element that is selected from IA group elements, IIA group elements, IIIA group elements, IIIB group elements except Al, rare-earth elements, and IVB group elements. x1, y, z, u, and w satisfy the following relationship. 0<x1?1, ?0.1?y?0.15, ?1?z?1, ?1<u?w?1.

Abstract: The present invention provides a fluorescent substance excellent both in quantum efficiency and in temperature characteristics, and also provides a process for producing the fluorescent substance. This fluorescent substance is an oxynitride phosphor having a low paramagnetic defect density and comprising aluminum, silicon, either or both of oxygen and nitrogen, and a metal element M, provided that the metal element M is partly replaced with an emission center element R. That phosphor can be produced by the steps of: subjecting a mixture of starting materials to heat treatment under a nitrogen atmosphere so as to obtain an intermediate fired product, and then further subjecting the intermediate fired product to heat treatment under an atmosphere of nitrogen-hydrogen mixed gas.

Abstract: A luminescent material is provided, which includes a carbide oxynitride-based compound having a composition represented by formula 1: (M1?wRw)uAl1?xSi1+vOzNtCy??formula 1 wherein M is at least one metal element excluding Si and Al, and R is a luminescent central element. w, u, x, v, z, t and y satisfy following relationships: 0.001<w<0.5; 0.66?u?1; 0.07?x?0.73; 0.06?v?0.84; 0.04?z?0.44; 2.7?t?3.1; and 0.019?y?0.13.

Abstract: The embodiment provides a process for production of an oxynitride fluorescent substance. An compound containing In or Ga is adopted in the process as a material thereof. The red fluorescent substance produced by the process can be combined with a semiconductor light-emitting element, so as to be used in a light-emitting device or a light-emitting module.

Abstract: The embodiment provides a process for production of a green light-emitting oxynitride fluorescent material having Sr3Al3Si13O2N21 crystal structure, and also provides the fluorescent material produced by that process. An metal halide is adopted in the process as one of the starting material metal compounds. As the metal halide, a Ca or Na compound as well as a Sr compound can be preferably employed.

Abstract: A luminescent material which is featured in that it exhibits an emission peak at a wavelength ranging from 490 to 580 nm as it is excited by light having a wavelength ranging from 250 to 500 nm and that it has a composition represented by the following general formula (2): (M1-xRx)a2AlSib2Oc2Nd2??(2) (In the general formula (2), M is at least one metallic element excluding Si and Al, R is a luminescence center element, and x, a2, b2, c2 and d2 satisfy the following relationships: 0<x?1, 0.93<a2<1.3, 4.0<b2<5.8 0.6<c2<1, 6<d2<11).

Abstract: A luminescent material which is featured in that it exhibits an emission peak at a wavelength ranging from 490 to 580 nm as it is excited by light having a wavelength ranging from 250 to 500 nm and that it has a composition represented by the following general formula (2): (M1-xRx)a2AlSib2Oc2Nd2 ??(2) (In the general formula (2), M is at least one metallic element excluding Si and Al, R is a luminescence center element, and x, a2, b2, c2 and d2 satisfy the following relationships: 0<x?1, 0.93<a2<1.3, 4.0<b2<5.8 0.6<c2<1, 6<d2<11).

Abstract: A luminescent material which is featured in that it exhibits an emission peak at a wavelength ranging from 490 to 580 nm as it is excited by light having a wavelength ranging from 250 to 500 nm and that it has a composition represented by the following general formula (2): (M1-xRx)a2AlSib2Oc2Nd2??(2) (In the general formula (2), M is at least one metallic element excluding Si and Al, R is a luminescence center element, and x, a2, b2, c2 and d2 satisfy the following relationships: 0<x?1, 0.93<a2<1.3, 4.0<b2<5.8 0.6<c2<1, 6<d2<11).

Abstract: The present invention provides a red fluorescent substance and a light-emitting device utilizing the substance. This device less suffers from color drift even when working with high power. The light-emitting device comprises a blue LED, a green fluorescent substance of Sr3Al3Si13O2N21 activated with a luminescent center, and the red fluorescent substance. The red fluorescent substance contains an inorganic compound comprising a metal element M, a trivalent element M1 other than the M, a tetravalent element M2 other than the M, and nitrogen element. In the inorganic compound, the M is partly replaced with a luminescent center element EC. The red fluorescent substance has basically the same crystal structure as Sr2Al3Si7ON13. The red fluorescent substance emits luminescence having a peak in the range of 580 to 650 nm when excited with light of 250 to 500 nm.

Abstract: The present invention provides a fluorescent substance excellent both in quantum efficiency and in temperature characteristics, and also provides a light-emitting device utilizing the fluorescent substance. This fluorescent substance contains an inorganic compound comprising a metal element M, a trivalent element M1 other than the metal element M, a tetravalent element M2 other than the metal element M, and either or both of O and N. In the inorganic compound, the metal element M is partly replaced with a luminescence center element R. The crystal structure of the fluorescent substance is basically the same as Sr3Al3Si13O2N21, but the chemical bond lengths of M1-N and M2-N are within the range of ±15% based on those of Al—N and Si—N calculated from the lattice constants and atomic coordinates of Sr3Al3Si13O2N21, respectively. The fluorescent substance emits luminescence having a peak in the range of 490 to 580 nm when excited with light of 250 to 500 nm.

Abstract: A fluorescent substance is provided, with includes a matrix composed of a compound having an AlN polytypoid structure represented by the following general formula (1), and a luminescence center element: (Al,M)a(N,X)b??(1) wherein, M is at least one metal excluding Al, X is at least one non-metal excluding N, and a and b are positive values.

Abstract: A luminescent material which is featured in that it exhibits an emission peak at a wavelength ranging from 490 to 580 nm as it is excited by light having a wavelength ranging from 250 to 500 nm and that it has a composition represented by the following general formula (2): (M1-xRx)a2AlSib2Oc2Nd2??(2) (In the general formula (2), M is at least one metallic element excluding Si and Al, R is a luminescence center element, and x, a2, b2, c2 and d2 satisfy the following relationships: 0<x?1, 0.93<a2<1.3, 4.0<b2<5.8 0.6<c2<1, 6<d2<11).

Abstract: A luminescent material is provided, which includes a carbide oxynitride-based compound having a composition represented by formula 1: (M1?wRw)uAl1?xSi1+vOzNtCy??formula 1 wherein M is at least one metal element excluding Si and Al, and R is a luminescent central element. w, u, x, v, z, t and y satisfy following relationships: 0.001<w<0.5; 0.66?u?1; 0.07?x?0.73; 0.06?v?0.84; 0.04?z?0.44; 2.7?t?3.1; and 0.019?y?0.13.

Abstract: A fluorescent substance is provided, with includes a matrix composed of a compound having an AlN polytypoid structure represented by the following general formula (1), and a luminescence center element: (Al, M)a(N, X)b ??(1) wherein, M is at least one metal excluding Al, X is at least one non-metal excluding N, and a and b are positive values.