Nichia Corporation

Toshiyuki Hirai

Masahiko Sano

Takafumi Sugiyama

Toru Takasone

Shozo Taketomi

Hirofumi Oguri

Tomomi Fujii

Ryo Yamamoto

Keisuke Suzuki

Gentaro Tanaka

A ceramic complex including a first crystal phase containing a first rare earth aluminate fluorescent material containing an activating element and a first rare earth element that is different from the activating element, and a second crystal phase containing aluminum oxide, having a content of the first crystal phase in a range of 5% by volume or more and 40% by volume or less and a content of the second crystal phase in a range of 57% by volume or more and 95% by volume or less based on a total amount of the ceramic complex, having an average value of a second crystal diameter of the second crystal phase measured under the particular measurement condition of 12 μm or less, and having a QD value of 0.5 or less expressed by QD=(D−D)/(D+D), wherein Dand Dare defined in the disclosure.

Ceramic complex, light emitting device, and method for producing ceramic complex

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 μm to 1.3 μm, and an absolute maximum length of 90% or more by number of voids is in a range from 0.1 μm to 1.2 μm.

Rare earth aluminate sintered compact and method for producing rare earth aluminate sintered compact

Provided is a light emitting device, including a light emitting element having a light emission peak wavelength in a range of 380 nm or more and 500 nm or less, and a wavelength converting member including a ceramic composite including an inorganic fluorescent material having a light emission peak wavelength in a range of 510 nm or more and 570 nm or less and an inorganic oxide, and a translucent thin film having a physical film thickness in a range of 82 nm or more and 140 nm or less and a refractive index smaller than the refractive index of the ceramic composite, disposed on a light emission side of the ceramic composite, the translucent thin film including a fluoride containing at least one kind of an element selected from the group consisting of an alkali metal element, an alkaline earth metal element, and a Group 13 metal element.

Light emitting device

A method for producing a ceramic complex includes: preparing a raw material mixture that contains 5% by mass or more and 40% by mass or less of first rare earth aluminate fluorescent material particles containing an activating element and a first rare earth element different from the activating element, 0.1% by mass or more and 32% by mass or less of oxide particles containing a second rare earth element, and the balance of aluminum oxide particles, relative to 100% by mass of the total amount of the first rare earth aluminate fluorescent material particles, the oxide particles, and the aluminum oxide particles; preparing a molded body of the raw material mixture; and obtaining a sintered body by calcining the molded body in a temperature range of 1,550° C. or higher and 1,800° C. or lower.

Ceramic complex and method for producing the same

A fluorescent module includes a fluorescent member including a phosphor-containing layer, and a light reflecting layer disposed on the phosphor-containing layer. The phosphor-containing layer contains a YAG phosphor and a Ga-YAG phosphor within the same layer, the Ga-YAG phosphor being a phosphor in which a portion of the aluminum constituting the YAG phosphor is substituted with gallium. A volumetric ratio of the Ga-YAG phosphor to the entirety of the YAG phosphor and the Ga-YAG phosphor is in a range of 19.0% to 80%.

Fluorescent module and illumination device

A method for producing a ceramic composite includes: preparing a sintered body in a plate form containing a fluorescent material having a composition of a rare earth aluminate, and aluminum oxide; and eluting the aluminum oxide from the sintered body by contacting the sintered body with a basic substance, for example, contained in an alkali aqueous solution, and the dissolution amount of the fluorescent material eluted from the sintered body in the step of eluting the aluminum oxide is 0.5% by mass or less based on an amount of the fluorescent material contained in the sintered body as 100% by mass.

Method for producing ceramic composite

A fluorescent module includes a fluorescent member, a heat dissipation member, and an optical relaxation member. The fluorescent member includes a phosphor-containing layer, and a light reflecting layer. The fluorescent member is secured to the heat dissipation member so that the light reflecting layer is arranged between the phosphor-contacting layer and the heat dissipation member. The optical relaxation member is configured to absorb and/or diffuse light. The optical relaxation member is arranged with respect to the fluorescent member so that the light reflecting layer is arranged between the phosphor-containing layer and the optical relaxation member.

Growing community of inventors

Komatsushima, Japan

Toshiyuki Hirai