Abstract: A rare earth aluminate sintered compact including rare earth aluminate phosphor crystalline phases and voids, wherein an absolute maximum length of 90% or more by number of rare earth aluminate phosphor crystalline phases is in a range from 0.4 ?m to 1.3 ?m, and an absolute maximum length of 90% or more by number of voids is in a range from 0.1 ?m to 1.2 ?m.

Abstract: A sintered body includes an aluminum oxide phase and crystal agglomerated particles containing a rare earth aluminate fluorescent material crystal phase, wherein the aluminum oxide phase is disposed around the crystal agglomerated particles. A method for producing a sintered body includes: providing a first mixture obtained by wet mixing raw materials and then drying; dry mixing the first mixture and aluminum oxide particles; molding a mixture obtained by dry mixing the first raw material mixture and the aluminum oxide particles; and calcining a molded body obtained by molding the mixture.

Abstract: A method for producing a rare earth aluminate sintered body includes: preparing a molded body by mixing a fluorescent material having a composition of a rare earth aluminate and a raw material mixture comprising an oxide containing at least one rare earth element Ln selected from the group consisting of Y, La, Lu, Gd, and Tb, an oxide containing Ce, an oxide containing Al, and optionally an oxide containing at least one element M1 selected from the group consisting of Ga and Sc; and calcining the molded body to obtain a sintered body.

Abstract: A rare earth aluminate sintered compact including rare earth aluminate phosphor crystalline phases and voids, wherein an absolute maximum length of 90% or more by number of rare earth aluminate phosphor crystalline phases is in a range from 0.4 ?m to 1.3 ?m, and an absolute maximum length of 90% or more by number of voids is in a range from 0.1 ?m to 1.2 ?m.

Abstract: A rare earth aluminate sintered body includes crystal agglomerated particles containing a rare earth aluminate fluorescent material crystal phase, and a rare earth aluminate crystal phase having a refractive index different from that of the rare earth aluminate fluorescent material crystal phase, wherein the rare earth aluminate crystal phase is arranged around the crystal agglomerated particles.

Abstract: A ceramic complex that has improved optical characteristics including luminous efficiency is provided. A method for producing a ceramic complex, including: preparing a molded body containing rare earth aluminum garnet fluorescent material, aluminum oxide, and lutetium oxide, and having a content of the rare earth aluminum garnet fluorescent material in a range of 15% by mass or more and 50% by mass or less, and a content of the lutetium oxide in a range of 0.2% by mass or more and 4.5% by mass or less, based on the total amount of the rare earth aluminum garnet fluorescent material, the aluminum oxide, and the lutetium oxide; and calcining the molded body in an air atmosphere to provide a ceramic complex having a relative density in a range of 90% or more and less than 100%.

Abstract: A rare earth aluminate sintered compact including rare earth aluminate phosphor crystalline phases and voids, wherein an absolute maximum length of 90% or more by number of rare earth aluminate phosphor crystalline phases is in a range from 0.4 ?m to 1.3 ?m, and an absolute maximum length of 90% or more by number of voids is in a range from 0.1 ?m to 1.2 ?m.

Abstract: Provided are a ceramic complex capable of improving the luminous efficiency, a projector comprising a ceramic complex, and a method for producing a ceramic complex. Proposed is a ceramic complex including a rare earth aluminate fluorescent material having an average particle diameter in a range of 15 ?m or more and 40 ?m or less, aluminum oxide having a purity of aluminum oxide of 99.0% by mass or more, and voids, wherein the content of the rare earth aluminate fluorescent material is in a range of 15% by mass or more and 50% by mass or less relative to a total amount of the rare earth aluminate fluorescent material and the aluminum oxide, and a void fraction is in a range of 1% or more and 10% or less.

Abstract: Provided are a method of producing an aluminate fluorescent material, an aluminate fluorescent material and a light emitting device. The production method includes heat-treating a mixture prepared by mixing a compound containing at least one alkaline earth metal element selected from the group consisting of Ba, Sr and Ca, a Mg-containing compound not acting as a flux, a Mn-containing compound, an Al-containing compound, a first flux containing at least one alkali metal element selected from the group consisting of Na, K, Rb and Cs, and a Mg-containing second flux to give an aluminate fluorescent material.

Abstract: A method for producing a rare earth aluminate sintered body includes: preparing a molded body by mixing a fluorescent material having a composition of a rare earth aluminate and a raw material mixture comprising an oxide containing at least one rare earth element Ln selected from the group consisting of Y, La, Lu, Gd, and Tb, an oxide containing Ce, an oxide containing Al, and optionally an oxide containing at least one element M1 selected from the group consisting of Ga and Sc; and calcining the molded body to obtain a sintered body.

Abstract: A ceramic complex that has improved optical characteristics including luminous efficiency is provided. A method for producing a ceramic complex, including: preparing a molded body containing rare earth aluminum garnet fluorescent material, aluminum oxide, and lutetium oxide, and having a content of the rare earth aluminum garnet fluorescent material in a range of 15% by mass or more and 50% by mass or less, and a content of the lutetium oxide in a range of 0.2% by mass or more and 4.5% by mass or less, based on the total amount of the rare earth aluminum garnet fluorescent material, the aluminum oxide, and the lutetium oxide; and calcining the molded body in an air atmosphere to provide a ceramic complex having a relative density in a range of 90% or more and less than 100%.

Abstract: Provided are a method of producing an aluminate fluorescent material, an aluminate fluorescent material and a light emitting device. The production method includes heat-treating a mixture prepared by mixing a compound containing at least one alkaline earth metal element selected from the group consisting of Ba, Sr and Ca, a Mg-containing compound not acting as a flux, a Mn-containing compound, an Al-containing compound, a first flux containing at least one alkali metal element selected from the group consisting of Na, K, Rb and Cs, and a Mg-containing second flux to give an aluminate fluorescent material.

Abstract: Provided are a ceramic complex capable of improving the luminous efficiency, a projector comprising a ceramic complex, and a method for producing a ceramic complex. Proposed is a ceramic complex including a rare earth aluminate fluorescent material having an average particle diameter in a range of 15 m or more and 40 ?m or less, aluminum oxide having a purity of aluminum oxide of 99.0% by mass or more, and voids, wherein the content of the rare earth aluminate fluorescent material is in a range of 15% by mass or more and 50% by mass or less relative to a total amount of the rare earth aluminate fluorescent material and the aluminum oxide, and a void fraction is in a range of 1% or more and 10% or less.

Abstract: Provided are a method of producing an aluminate fluorescent material, an aluminate fluorescent material and a light emitting device. The production method includes heat-treating a mixture prepared by mixing a compound containing at least one alkaline earth metal element selected from the group consisting of Ba, Sr and Ca, a Mg-containing compound not acting as a flux, a Mn-containing compound, an Al-containing compound, a first flux containing at least one alkali metal element selected from the group consisting of Na, K, Rb and Cs, and a Mg-containing second flux to give an aluminate fluorescent material.

Abstract: Provided are a method of producing an aluminate fluorescent material, an aluminate fluorescent material and a light emitting device. The production method includes heat-treating a mixture prepared by mixing a compound containing at least one alkaline earth metal element selected from the group consisting of Ba, Sr and Ca, a Mg-containing compound not acting as a flux, a Mn-containing compound, an Al-containing compound, a first flux containing at least one alkali metal element selected from the group consisting of Na, K, Rb and Cs, and a Mg-containing second flux to give an aluminate fluorescent material.