Ngk Spark Plug Company, Limited

Niterra Co., Ltd.

Tsuneyuki Ito

Yusuke Katsu

Shohei Takaku

Takeshi Mitsuoka

Jun Moteki

Hideto Yamada

Toshiaki Kurahashi

Yuki Shimura

Osamu Yoshimoto

Tomoo Tanaka

Shinji Ban

Syohei Takaku

Katsu Yusuke

A ceramic sintered body contains a first particular element consisting of five or six elements selected from among titanium (Ti), vanadium (V), zirconium (Zr), niobium (Nb), molybdenum (Mo), hafnium (Hf), tantalum (Ta), and tungsten (W); a second particular element consisting of one element selected from yttrium (Y) and aluminum (Al); and elemental carbon (C). The total amount of the first particular element, the second particular element, and elemental carbon is 98 at % or more. The ceramic sintered body has a plurality of microstructures having respective compositions different from one another. One of the plurality of microstructures includes a solid solution containing at least three members of the first particular element.

Ceramic sintered body and plasma-generating electrode

In one aspect of the present disclosure, there is provided an optical wavelength conversion member including a polycrystalline ceramic sintered body containing, as main components, AlOcrystal grains and crystal grains represented by formula XAlO:Ce. In the optical wavelength conversion member, atoms of element X are present also in an AlOcrystal grain adjacent to the interface between the AlOcrystal grain and an XAlO:Ce crystal grain.

Light wavelength conversion member and light-emitting device

One aspect of the disclosure provides an optical wavelength conversion member including a polycrystalline ceramic sintered body containing, as main components, AlOcrystal grains and crystal grains represented by formula (Y,A)BO:Ce. In the optical wavelength conversion member, a (Y,A)BO:Ce crystal grain has a region wherein the A concentration of a peripheral portion of the (Y,A)BO:Ce crystal grain is higher than that of an interior portion of the (Y,A)BO:Ce crystal grain. Thus, the optical wavelength conversion member exhibits high fluorescence intensity (i.e., high emission intensity) and high heat resistance (i.e., low likelihood of temperature quenching). The optical wavelength conversion member has a structure wherein the element A concentration of a peripheral portion of a (Y,A)BO:Ce crystal grain differs from that in an interior portion of the crystal grain. This structure can achieve a ceramic fluorescent body exhibiting superior fluorescent characteristics and superior thermal characteristics with varied colors of emitted light.

Optical wavelength conversion member and light-emitting device

An optical wavelength converter () is configured such that an optical wavelength conversion member () is bonded to a heat dissipation member () having superior heat dissipation property. Thus, heat generated by light incident on the optical wavelength conversion member () can be efficiently dissipated. Therefore, even when high-energy light is incident on the optical wavelength converter, temperature quenching is less likely to occur, and thus high fluorescence intensity can be maintained. An intermediate film () is disposed between a reflective film () and a bonding portion (). The presence of the intermediate film () improves the adhesion between the reflective film () and the bonding portion (), thereby enhancing the heat dissipation from the optical wavelength conversion member () to the heat dissipation member (). Thus, the temperature quenching of the optical wavelength conversion member () can be prevented, thereby enhancing fluorescence intensity.

Optical wavelength converter and composite optical device

An optical wavelength conversion member () provided with a ceramic plate () which is configured from a polycrystalline body that is mainly composed of AlOand a component represented by ABO:Ce; and each of A and B in ABOrepresents at least one element selected from the element groups described below. In addition, a dielectric multilayer film () which transmits a specific wavelength and reflects another specific wavelength is formed on a light incident surface () of the ceramic plate (). The ceramic plate () has a porosity of 2% by volume or less, while having an average surface roughness (an arithmetic mean roughness Sa) of 0.5 &#x3bc;m or less. A: Sc, Y and lanthanoids (excluding Ce) B: Al and Ga. Also disclosed is a light-emitting device including the optical wavelength conversion member.

Light wavelength conversion member and light emitting device

A method for producing an optical wavelength conversion member () composed of a sintered body containing, as main components, AlOand a component represented by formula ABO:Ce; an optical wavelength conversion member; an optical wavelength conversion component including the optical wavelength conversion member; and a light-emitting device including the optical wavelength conversion member or the optical wavelength conversion component. The production method of the sintered body includes firing in a firing atmosphere having a pressure of 10Pa or more and an oxygen concentration of 0.8 vol. % or more and less than 25 vol. %.

Method for producing light wavelength conversion member, light wavelength conversion member, light wavelength conversion component and light emitting device

An optical wavelength conversion member and a light-emitting device including the optical wavelength conversion member. The light-emitting device () includes a container (), a light-emitting element (), and an optical wavelength conversion member (). The optical wavelength conversion member () is composed of a polycrystalline ceramic sintered body containing, as main components, AlOcrystal grains and crystal grains of a component represented by formula ABO:Ce. Specifically, A and B of the ABOindividually represent at least one element selected from the following element groups: A: Sc, Y, and lanthanoids (except for Ce), and B: Al and Ga; the at least one element selected from the element groups is present in each crystal grain and the crystal grain boundary of the ceramic sintered body; and the element concentration of the crystal grain boundary is higher than the element concentration of the crystal grain.

An optical wavelength conversion member and a light-emitting device including the optical wavelength conversion member. The optical wavelength conversion member () is formed of a ceramic sintered body having a fluorescent phase containing fluorescent crystal grains as a main component and a translucent phase containing translucent crystal grains as a main component. Crystal grains of the fluorescent phase have a composition represented by formula ABO:Ce, where the element A is selected from Sc, Y, and lanthanoids (except for Ce), and the element B is selected from Al and Ga. In the optical wavelength conversion member (), 0.3&#x3c;a&#x3c;34 and 300 &#x3bc;m&#x3c;y&#x3c;1,050 &#x3bc;m are satisfied, wherein a represents the area ratio of the translucent phase to the fluorescent phase in a cross section of the optical wavelength conversion member (), and y represents the interfacial length of the fluorescent phase.

An optical wavelength conversion member including a polycrystalline ceramic sintered body containing, as main components, AlOcrystal grains and crystal grains of a component represented by formula ABO:Ce, wherein A is at least one element selected from Sc, Y and lanthanoids (except for Ce), and B is at least one element selected from Al and Ga. Further, the following relations are satisfied: 0%&#x2264;X&#x2264;25%, 9%&#x2264;Y&#x2264;45%, and 48%&#x2264;Z&#x2264;90%, wherein X represents a proportion corresponding to the ratio a/N, Y represents a proportion corresponding to the ratio b/N, and Z represents a proportion corresponding to the ratio c/N and a, b, c and N are as defined herein. Also disclosed is a light-emitting device including the optical wavelength conversion member.

Growing community of inventors

Aichi, Japan

Tsuneyuki Ito