Search Results - "Takahashi, Kohsei"

Highly efficient narrow-band green and red phosphors enabling wider color-gamut LED backlight for more brilliant displays by Wang, Le, Wang, Xiaojun, Kohsei, Takahashi, Yoshimura, Ken-ichi, Izumi, Makoto, Hirosaki, Naoto, Xie, Rong-Jun

“…In this contribution, we propose to combine both narrow-band green (β-sialon:Eu(2+)) and red (K(2)SiF(6):Mn(4+)) phosphors with a blue InGaN chip to achieve…”
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Thermal Quenching Mechanism of CaAlSiN3:Eu2+ Red Phosphor by Ueda, Jumpei, Tanabe, Setsuhisa, Takahashi, Kohsei, Takeda, Takashi, Hirosaki, Naoto

“…CaAlSiN3:Eu2+ is a widely applied phosphor in white LEDs (w-LEDs) because of strong blue absorption and efficient red luminescence with high thermal quenching…”
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Robust and orange-yellow-emitting Sr-rich polytypoid α-SiAlON (Sr 3 Si 24 Al 6 N 40 :Eu 2+ ) phosphor for white LEDs by Estili, Mehdi, Xie, Rong-Jun, Takahashi, Kohsei, Funahashi, Shiro, Suzuki, Tohru S, Hirosaki, Naoto

“…Nitrides and oxynitrides isostructural to α-Si N ( -α-SiAlON,  = Sr, Ca, Li) possess superb thermally stable photoluminescence (PL) properties, making them…”
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Ce-Doped La3Si6.5Al1.5N9.5O5.5, a Rare Highly Efficient Blue-Emitting Phosphor at Short Wavelength toward High Color Rendering White LED Application by Wang, Chun-Yun, Takeda, Takashi, ten Kate, Otmar Melvin, Tansho, Masataka, Deguchi, Kenzo, Takahashi, Kohsei, Xie, Rong-Jun, Shimizu, Tadashi, Hirosaki, Naoto

“…Phase pure nondoped and Ce doped La3Si6.5Al1.5N9.5O5.5 (Al containing La N-phase) samples have been obtained by solid-state reaction synthesis for the first…”
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Mo6 cluster-based compounds for energy conversion applications: comparative study of photoluminescence and cathodoluminescence by Dierre, Benjamin, Costuas, Karine, Dumait, Noée, Paofai, Serge, Amela-Cortes, Maria, Molard, Yann, Grasset, Fabien, Cho, Yujin, Takahashi, Kohsei, Ohashi, Naoki, Uchikoshi, Tetsuo, Cordier, Stéphane

“…We report the photoluminescence (PL) and cathodoluminescence (CL) properties of face-capped [Mo 6 X i 8 L a 6 ] 2− (X = Cl, Br, I; L = organic or inorganic…”
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New Deep-Blue-Emitting Ce-Doped A4-mBnC19+2mX29+m (A = Sr, La; B = Li; C = Si, Al; X = O, N; 0 ≤ m ≤ 1; 0 ≤ n ≤ 1) Phosphors for High-Color-Rendering Warm White Light-Emitting Diodes by Wang, Chun-Yun, Takeda, Takashi, Melvin Ten Kate, Otmar, Funahashi, Shiro, Xie, Rong-Jun, Takahashi, Kohsei, Hirosaki, Naoto

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Optical properties of solid-state laser lighting devices using SiAlON phosphor-glass composite films as wavelength converters by Yoshimura, Kenichi, Annen, Kazunori, Fukunaga, Hiroshi, Harada, Masamichi, Izumi, Makoto, Takahashi, Kohsei, Uchikoshi, Tetsuo, Xie, Rong-Jun, Hirosaki, Naoto

“…In this work, SiAlON phosphor-glass films were investigated as wavelength converters in solid-state laser lighting. The phosphor-glass composite films were…”
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Thermal Relaxation Spectra for Evaluating Luminescence Quantum Efficiency of CASN:Eu2+ Measured by Balanced-Detection Sagnac-Interferometer Photothermal Deflection Spectroscopy by Chima, Hiromichi, Shiokawa, Naoyuki, Seto, Keisuke, Takahashi, Kohsei, Hirosaki, Naoto, Kobayashi, Takayoshi, Tokunaga, Eiji

“…Highly sensitive broadband photothermal spectroscopy with a white-light lamp as the excitation source was developed by combining a Sagnac interferometer and…”
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Visible tunable lighting system based on polymer composites embedding ZnO and metallic clusters: from colloids to thin films by Truong, Thai Giang, Dierre, Benjamin, Grasset, Fabien, Saito, Noriko, Saito, Norio, Nguyen, Thi Kim Ngan, Takahashi, Kohsei, Uchikoshi, Tetsuo, Amela-Cortes, Marian, Molard, Yann, Cordier, Stéphane, Ohashi, Naoki

“…The development of phosphor devices free of heavy metal or rare earth elements is an important issue for environmental reasons and energy efficiency. Different…”
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Microanalysis of Calcium Codoped LaAl(Si6−zAlz)(N10−zOz) (z~1): Ce3+ Blue Phosphor by Takahashi, Kohsei, Dierre, Benjamin, Cho, Yujin, Sekiguchi, Takashi, Xie, Rong-Jun, Hirosaki, Naoto

“…Cathodoluminescence spectra of Ca codoped (La,Ce)Al(Si6−zAlz)(N10−zOz) (z~1) (termed JEM phase) phosphors were analyzed microscopically. The as‐prepared…”
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Nitride phosphors as robust emissive materials in white flat field emission lamps by Wang, Le, Wang, Xiao-Jun, Takahashi, Kohsei, Takeda, Takashi, Hirosaki, Naoto, Xie, Rong-Jun

“…Nitride phosphors, showing very promising photoluminescence properties, are now attracting great attention as down-conversion luminescent materials in white…”
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On the origin of fine structure in the photoluminescence spectra of the β-sialon:Eu2+ green phosphor by Takahashi, Kohsei, Yoshimura, Ken-ichi, Harada, Masamichi, Tomomura, Yoshitaka, Takeda, Takashi, Xie, Rong-Jun, Hirosaki, Naoto

“…The photoluminescence (PL) and PL excitation (PLE) spectra of Si 6−z Al z O z N 8−z (β-sialon):Eu 2+ phosphors with small z values (z=0.025-0.24) were studied…”
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Local analysis of Eu2+ emission in CaAlSiN3 by Dierre, Benjamin, Takeda, Takashi, Sekiguchi, Takashi, Suehiro, Takayuki, Takahashi, Kohsei, Yamamoto, Yoshinobu, Xie, Rong-Jun, Hirosaki, Naoto

“…We have investigated the local luminescence properties of Eu-doped CaAlSiN 3 by using low-energy electron beam (e-beam) techniques. The particles yield broad…”
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Luminescence of single-particle ceramic phosphor by proximity measurement by Takahashi, Kohsei, Takeda, Takashi, Hirosaki, Naoto

“…Abstract A simple method for measuring the luminescence of a single-particle phosphor was developed. Optical fibers for excitation and detection were placed in…”
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Elucidating photoluminescent properties of Eu‐doped Ca–Al–Si–O(–N) glasses and the local structures of Eu ions by Segawa, Hiroyo, Wójcik, Natalia A., Takahashi, Kohsei, Takeda, Takashi, Ali, Sharafat

“…Europium (Eu) ion–doped luminescent materials have attracted considerable attention for their numerous optical applications. Eu‐doped Ca–Al–Si–O(–N) glasses…”
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Structure elucidation of luminescent centers in green emitting Eu2+ doped Si6-zAlzOzN8-z phosphors by Takeda, Takashi, Funahashi, Shiro, Takahashi, Kohsei, Xie, Rong-Jun, Hirosaki, Naoto

“…Eu2+ doped Si6-zAlzOzN8-z (β-sialon) is a common green emitting phosphor used in white light emitting diodes. Due to its narrowband emission, a wide color…”
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Unraveling the Luminescence Quenching of Phosphors under High-Power-Density Excitation by Zheng, Peng, Li, Shuxing, Takeda, Takashi, Xu, Jian, Takahashi, Kohsei, Tian, Rundong, Wei, Ran, Wang, Le, Zhou, Tian-Liang, Hirosaki, Naoto, Xie, Rong-Jun

“…Laser-driven phosphor-converted white light sources have received great attention for next-generation high-brightness lighting and display technologies…”
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Investigation of luminescence properties of Eu-doped Si-Al-O-N glasses synthesized via sol-gel process by Watanabe, Shunsuke, Osawa, Yuta, Machida, Shingo, Katsumata, Ken-ichi, Yasumori, Atsuo, Takahashi, Kohsei, Deguchi, Kenzo, Ohki, Shinobu, Segawa, Hiroyo

“…Luminescent properties of Eu ions doped in Si-Al oxynitride glasses were investigated. The Si-Al oxynitride glasses contained with Eu ions were prepared via…”
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Achieving superwide-color-gamut display by using narrow-band green-emitting γ-AlON:Mn,Mg phosphor by Yoshimura, Kenichi, Fukunaga, Hiroshi, Izumi, Makoto, Takahashi, Kohsei, Xie, Rong-Jun, Hirosaki, Naoto

“…The display backlight generated using sharp β-sialon:Eu (green) and K2SiF6:Mn (red) phosphors shows a very wide color gamut that mostly covers the whole…”
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Effect of shock compression on luminescence properties of CsAlSi2O6:Eu2+ for white-light-emitting diodes by Hamada, Sho, Kishimura, Hiroaki, Matsumoto, Hitoshi, Takahashi, Kohsei, Aruga, Atsushi

“…Eu2+-doped CsAlSi2O6 (pollucite) phosphors were synthesized via high-temperature solid-state reaction to produce a white-light-emitting phosphor under UV…”
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