Kabushiki Kaisha Toshiba

Toshiba Materials Co., Ltd.

Seoul Semiconductor Co., Ltd.

Yoshitaka Funayama

Tsutomu Ishii

Yasuhiro Shirakawa

Yasumasa Ooya

Katsutoshi Nakagawa

Ryo Sakai

Naotoshi Matsuda

Hajime Takeuchi

Ryoji Tsuda

Yumi Ito

Tatsunori Itoga

Hirofumi Takemura

Yukihiro Fukuta

Daichi Usui

Hiroyasu Oota

Yumi Kanno

According to one embodiment, a white light source includes a combination of a light emitting diode and phosphors. One of the phosphors is at least a cerium activated yttrium aluminum garnet-based phosphor. There is no light emission spectrum peak at which a ratio of a largest maximum value to a minimum value is greater than 1.9. The largest maximum value is largest among at least one maximum value present in a wavelength range of 400 nm to 500 nm in a light emission spectrum of white light emitted from the white light source. The minimum value is adjacent to the largest maximum value in a longer wavelength side of the light emission spectrum.

White light source including LED and phosphors

A phosphor has a composition represented by Chemical formula 1: 1.5YO&#xb7;2.5aAlO:Ce where a is a number satisfying 1.02&#x3c;a&#x3c;1.1.

Phosphor and method of manufacturing same, and LED lamp

An LED light emitting device is provided that has high color rendering properties and is excellent color uniformity and, at the same time, can realize even luminescence unattainable by conventional techniques. A phosphor having a composition represented by formula: (SrBaMgMnEu)SiOwherein x, y, z, and &#x3c9; are respectively coefficients satisfying 0.1&#x3c;x&#x3c;1, 0&#x3c;y&#x3c;0.5, 0&#x3c;z&#x3c;0.1, y&#x3e;z, and 0.01&#x3c;&#x3c9;&#x3c;0.2 is provided. The phosphor is used in combination with ultraviolet and blue light emitting diodes having a luminescence peak wavelength of 360 to 470 nm to form an LED light emitting device.

Phosphor and LED light emitting device using the same

A phosphor for light emitting device of an embodiment includes: a phosphor particle composed of at least one selected from an alkaline earth silicate phosphor, a lanthanum oxysulfide phosphor, and a zinc sulfide phosphor; and a surface treatment agent, provided to cover a surface of the phosphor particle, of at least one selected from a silane coupling agent and an acrylic emulsion. A luminance maintenance ratio of the phosphor represented by a formula: luminance B/luminance A&#xd7;100(%), is 98% or more, wherein the luminance A is a luminance of the phosphor made to emit under a condition of temperature: 23&#xb0; C., humidity: 40%, and the luminance B is a luminance of the phosphor made to emit under a condition of temperature: 23&#xb0; C., humidity: 40% after leaving the phosphor under a condition of temperature: 60&#xb0; C., humidity: 90% for 12 hours.

Phosphor for light emitting device and method for manufacturing the same, and light emitting device using the same

A light emitting deviceaccording to an embodiment includes a planar alumina substrate, a semiconductor light-emitting element mounted on the alumina substrate, and a phosphor layer. The phosphor layer includes a silicone resin layer provided to cover an upper surface and a side surface of the semiconductor light-emitting element and a phosphor emitting visible light by being excited with light emitted from the semiconductor light-emitting element. The phosphor is dispersed in the silicone resin layer. The alumina substrate has a water absorption rate of 5% or more and 60% or less, and an adhesion strength between the alumina substrate and the silicone resin layer is 1 N or more.

Light emitting device

Phosphor and LED light-emitting device using the same

A solid scintillator having short afterglow and high output, containing a polycrystal containing a crystal of a Gd garnet structure oxide having a composition ratio of formula (1):(MGdQ)JO&#x2003;&#x2003;(1)where M is at least one element of La and Tb, Q is at least one element of Ce and Pr, J is at least one element selected from Al, Ga, and In, x and y satisfy the relations 0.5&#x2266;x&#x3c;1, and 0.000001&#x2266;y&#x2266;0.2, and further containing Si and fluorine, where the solid scintillator contains 1 ppm by mass to 1000 ppm by mass of the Si with respect to the Gd garnet structure oxide, and 1 ppm by mass to 100 ppm by mass of the fluorine with respect to the Gd garnet structure oxide. In addition a radiation detector and a tomograph employing the solid scintillator.

Solid scintillator, radiation detector, and tomograph

Growing community of inventors

Yokohama, Japan

Yoshitaka Funayama