Papers - Koike, Yasuhiro

High-Bandwidth Graded-Index Polymer Optical Fiber

ISHIGURE TAKAAKI, NIHEI EISUKE, KOIKE YASUHIRO

Journal of Lightwave Technology, Vol.13 ( No.7 ) 1475-1489 1995.07

Research paper (scientific journal), Joint Work, Accepted

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High-bandwidth (2GHz km) GI POF was successfully obtained by the new interfacial-gel polymerization technique in which the unreactive component was used in order to obtain the quadratic refractive index distribution. This high-bandwidth GI POF makes it possible to transmit high-speed optical signals in the short range network which was not covered by SI type POF commercially available. The high-bandwidth GIPOF will open the way for great advantage in the high-speed multimedia network.

High Bandwidth Polymer Optical Fiber

KOIKE YASUHIRO

Electronics and Communications in Japan (The Institute os Electronics. Information and Communication Engineers)  Vol.78 ( No.6 ) 560-564 1995.06

Research paper (other academic), Single Work

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広帯域な特性を有するポリマー光ファイバーについて、その構造と伝送特性について明らかにした。（解説）

Most Transparent Polymer

KOIKE YASUHIRO

高分子/高分子学会誌 (The Society of Polymer Science, Japan)  44 ( 6月 ) 388-389 1995.06

Research paper (other academic), Single Work

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POFの開発研究をもとに、最も光をよく通す高分子について平易に解説した。

High-Power Polymer Optical Fiber Amplifier

YAMAMOTO TSUYOSHI, FUJII KAZUHITO, TAGAYA AKIHIRO, TERAMOTO SHIGEHIRO, NIHEI EISUKE, KOIKEYASUHIRO, SASAKI KEISUKE

The Journal of The Institute of Electronics,Information and Communication Engineers,(Electronics and Communications in Japan,) (電子情報通信学会)  Vol.J78-C-I ( No.6 ) 282-288 1995.06

Research paper (scientific journal), Joint Work

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屈折率分布型ポリマー光ファイバーアンプに用いる有機色素を変えることにより、可視光領域における任意の波長の信号光の増幅の可能性を明らかにした。実験では用いる有機色素をローダミン6G、ローダミンB、ペリレンレッドと変えることにより、３つの信号光波長（571、591、621nm)での増幅現象を確認した。

ポリマー光ファイバー

KOIKE YASUHIRO

Japanese Journal of Optics (Optical Society of Japan, (An Affiliate of The Japan Society of Applied physics))  第24 ( 第5 ) 286-287 1995.05

Research paper (scientific journal), Single Work

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近年シングルモード(SM)型のガラスファイバーが長距離幹線系に広く用いられ、Gbpsオーダーの高速通信が現実に行われるようになってきた。更に各家庭にまで高速情報を送り込むfiber to the home(FTTH)、LANを中心とした高速情報化社会に向けての研究が行われている。本稿では高速通信のためのポリマー光ファイバー（POF)について解説した。

Large-Core,High-Bandwidth Polymer Optical Fiber for Near Infrared Use

ISHIGURE TAKAAKI,NIHEI EISUKE, KOIKE YASUHIRO, CHARLES E. FORBES, LESLIE LALIEVE, RICH STRAFF, HELLMUTH A. DECKERS

IEEE Photonics Technology Letters Vol.7, ( NO.4, ) 403-405 1995.04

Research paper (scientific journal), Joint Work, Accepted

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High bandwidth (more than 500 MHz km) GI POF for near infra-red use was successfully fabricated by using partially fluorinated acrylate monomer. Since only three carbon-hydrogen bonds exist in a monomer unit, an absorption loss due to the stretching vibration of the carbon-hydrogen bonds was remarkably reduced compared with the conventional POF’s. The attenuation of the GI POF at 780 nm wavelength was 135dB/km, which is much lower than that of the PMMA core POF (800dB/km). The fluorinated polymer-based GI POF is satisfying a significant segment of high-speed multimedia network applications.

2.5Gbit/s 100m Data Transmission Using Graded-Index Polymer Oprical Fibre and High-Speed Laser Diode at 650nm Wavelength

ISHIGURE TAKAAKI, NIHEI EISUKE, YAMAZAKI SHUNTAROU, KOBAYASHI KENICHI, KOIKE YASUHIRO

Electronics Letters Vol.31 ( No.6 ) 467-468 1995.03

Research paper (scientific journal), Joint Work, Accepted

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High-bandwidth GI POF has been successfully obtained which realizes 2.5 Gbit/s signal transmission over 100m spans for the first time by using a 650nm high-speed laser diode. In the letter the advantage of the GI POF for high-speed short-range optical communication is described.

Basic Performance of An Organic Dye-Doped Polymer Oprical Fiber Amplifier

TAGAYA AKIHIRO, KOIKE YASUHIRO, NIHEI EISUKE, TERAMOTO SHIGEHIRO, FUJII KAZUHITO, YAMAMOTO TSUYOSHI, SASAKI KEISUKE

Applied Optics Vol.34 ( No.6 ) 988-992 1995.02

Research paper (scientific journal), Joint Work, Accepted

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A POFA of the GI type, with gain in the visible region, was successfully prepared for the first time, to our knowledge, with the interfacial-gel polymerization technique. An input signal of 0.85 W at 591 nm was amplified to 420 W (27dB gain) by injection of 690 W of pump power at523 nm in to a GI POFA with a 0.5m length. The efficiency of conversion of pump energy to signal amplification was more than 60%.

Polymer Optical Fiber Amplifier

TAGAYA AKIHIRO, KOIKEYASUHIRO, SASAKI KEISUKE

応用物理/応用物理学会誌 (The Japan Society of Applied Physics)  第64 ( 第1 ) 32-35 1995.01

Research paper (scientific journal), Joint Work

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著者らにより初めて提案された、プラスチック光ファイバー光増幅器という新規なデバイスを紹介した論文である。プラスチック光ファイバー光増幅器の作製方法、光増幅特性、理論解析などについて詳細に紹介している。

プラスチック光ファイバーと情報社会

KOIKE YASUHIRO

三田評論  1995.01

Research paper (other academic), Single Work

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広伝送帯域を実現する屈折率分布型ポリマー光ファイバーが、情報化社会でどのように利用されていくかを平易に解説。（解説）

The Large Dimensional Radial GRIN Polymer

SHAN PIN WO, NIHEI EISUKE, KOIKE YASUHIRO

Polymer Journal Vol.27 ( No.1 ) 21-25 1995.01

Research paper (scientific journal), Joint Work, Accepted

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A new method for preparing very large radial GRIN polymer plates is proposed . The resulting radial-GRIN plate has a diameter of 70mm of the GRIN region and Δn of 0.02. The optical characteristics of the large radial-GRIN lens were estimated by calculating the trajectory of a ray through GRIN lens which was based on Maxwell’s ray equation. It was confirmed that such large GRIN polymers are promising for eye glasses with no spherical aberration or multifocus properties.

Plastic Optical Fiber

KOIKE YUASHIRO, NIHEI EISUKE

繊維と工業/繊維学会誌 (The Society of Fiber Science and Technology, Japan)  第50 ( 12 ) 623-627 1994.12

Research paper (scientific journal), Joint Work

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これまでに開発されてきたプラスチック光ファイバーの経緯を示し、その種類、光学特性等を明らかにし、近未来の情報伝送媒体としての利用の可能性を明らかにしている。

マルチメディアへ向けてのＰＯＦ

KOIKE YASUHIRO

OPTORONICS (株式会社　オプトロニクス)   ( No.10 ) 101-106 1994.10

Research paper (scientific journal), Single Work

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マルチメディアにおけるＰＯＦの可能性を具体的に述べる。

High Bandwidth and High Numerical Aperture Graded-Index Polymer Optical Fiber

ISHIGURE TAKAAKI, HORIBE AKIHIRO, NIHEI EISUKE, KOIKE YASUHIRO

Electronics Letters Vol.30 ( No.14 ) 1169-1170 1994.07

Research paper (scientific journal), Joint Work, Accepted

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A large core (0.5-1.0mm), high-bandwidth (586MHz km), and low-loss (150dB/km at 650nm of wavelength) GI POF was successfully realized. The high index gradient Δn (0.028) resulted in a significant improvement in the bending loss for less than 50mm bending diameter compared with previous GI POFs.

Graded-Index Polymer Optial Fiber for High-Speed Data Communication

ISHIGURE TAKAAKI, NIHEI EISUKE, KOIKE YASUHIRO

Applied Optics Vol.33 ( No.19 ) 4261-4266 1994.07

Research paper (scientific journal), Joint Work, Accepted

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We successfully obtained a high-bandwidth (1GHz km) and low-loss (90dB/km at 0.572µm of wavelength) GI POF by using the interfacial-gel polymerization technique, in which we used an unreactive component to obtain the quadratic refractive-index distribution. This high-bandwidth GI POF makes it possible to transmit a high-speed optical signal in a short-rage network, which is not possible when we use the SI type of POF commercially available.

Spherical Gradient-Index Polymer Lens with Low Spherical Aberration

KOIKE YASUHIRO, KANEMITSU AKIYOSHI, NIHEI EISUKE, OHTSUKA YASUJI

Applied Optics Vol.33 ( No.16 ) 3394-3400 1994.06

Research paper (scientific journal), Joint Work, Accepted

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A sphere lens with a spherical GRIN was prepared by the modified suspension polymerization technique. GRIN spheres with quadratic- and linear-index distributions were obtained by two different methods to confirm the effect of the GRIN profile on the focusing property of the sphere lens. It was confirmed in both theory and experiment that the spherical aberration of such GRIN sphere was remarkably decreased compared with that of a homogenous sphere.

Highly Scattered Optical Transmission polymer

KOIKE YASUHIRO

高分子/高分子学会誌 (The Society of Polymer Science, Japan)  43 ( 4月 ) 291 1994.04

Research paper (scientific journal), Single Work

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ポリマー中に理論的にある条件を満足させるように不均一構造を形成させることで優れた光散乱特性を実現する方法を示した。

Polarization-Maintaining Optical lsolator Using Transparent Plastics with Optical Activity and Magnetooptical Property

TSUKAMOTO TOHRU, MUTO SHINZO, NIHEI EISUKE, KOIKE YASUHIRO

Kogaku(Japanese Joumal of Optics) Vol.23 ( No.3 ) 212-215 1994.03

Research paper (scientific journal), Joint Work

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In the copolymer of MMA and BzMA doped with TPED, a rotatory angle increased with increasing the TPED concentration and the Verdet constant increased with increasing the BzMA composition. A new plastic optical isolator which keeps the light beam polarization, was tested using this TPED-doped poly (MMA-BzMA) rod. The isolation of about 20dB was obtained though the insertion loss was high due to the light scattering caused by the dopant molecules.

Graded-Index Optical Polymer Materials and Its Applications

KOIKE YASUHIRO, NISHIZAWA YUKIE

CERAMICS JAPAN (日本セラミックス協会)  Vol.29 ( No.3 ) 194-196 1994.03

Research paper (other academic), Joint Work

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屈折率傾斜型ポリマー材料について、その作製方法や光学特性および光学材料への応用について解説する。

Measurement Method of Optical Properties

KOIKE YASUHIRO, NIHEI EISUKE

高分子/高分子学会誌 (The Society of Polymer Science, Japan)  43 ( 2月 ) 82-85 1994.02

Research paper (scientific journal), Joint Work

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高分子の光学特性の測定方法として、屈折率分布及び不均一構造について解説している。屈折率分布については、Maxwellの光線方程式をルンゲ?クッタ法を用いて直接数値積分して得られる結果と、実測して得られる結果とを一致させて求める方法を、ポリマー内部の不均一構造については、そのポリマーからの散乱光の角度依存性を測定し、これをデバイの式へ代入して求める方法を示している。（解説）