61 results on '"Yoshito Shuto"'
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2. Bending Induced Temperature Increases in Double-Clad Fibers for High-Power Fiber Lasers
- Author
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Yoshito Shuto
- Subjects
General Earth and Planetary Sciences ,General Environmental Science - Published
- 2022
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Catalog
3. Electron Density Estimation and Fiber Fuse Simulation in Laser-Irradiated Bulk Glass
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Yoshito Shuto
- Subjects
General Earth and Planetary Sciences ,General Environmental Science - Published
- 2022
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4. Cavity Formation Modeling of Fiber Fuse in Single-Mode Optical Fibers
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Yoshito Shuto
- Subjects
Optical fiber ,Materials science ,Article Subject ,lcsh:TK7800-8360 ,Physics::Optics ,02 engineering and technology ,Molecular physics ,law.invention ,020210 optoelectronics & photonics ,Optics ,law ,0202 electrical engineering, electronic engineering, information engineering ,lcsh:QC350-467 ,Fiber ,Electrical and Electronic Engineering ,Van der Pol oscillator ,business.industry ,Oscillation ,lcsh:Electronics ,Single-mode optical fiber ,Electronic, Optical and Magnetic Materials ,Core (optical fiber) ,Nonlinear system ,Relaxation (physics) ,business ,lcsh:Optics. Light - Abstract
The evolution of a fiber-fuse phenomenon in a single-mode optical fiber was studied theoretically. To clarify both the silica-glass densification and cavity formation, which have been observed in fiber fuse propagation, we investigated a nonlinear oscillation model using the Van Der Pol equation. This model was able to phenomenologically explain both the densification of the core material and the formation of periodic cavities in the core layer as a result of a relaxation oscillation. more...
- Published
- 2017
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5. Cavity Generation Modeling of Fiber Fuse in Single-Mode Optical Fibers
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Yoshito Shuto
- Subjects
InformationSystems_INFORMATIONSTORAGEANDRETRIEVAL ,GeneralLiterature_REFERENCE(e.g.,dictionaries,encyclopedias,glossaries) - Published
- 2019
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6. Simulation of fiber fuse phenomenon in photonic crystal fibers
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Yoshito Shuto
- Subjects
Optical fiber ,Materials science ,Physics::Optics ,02 engineering and technology ,01 natural sciences ,law.invention ,010309 optics ,020210 optoelectronics & photonics ,law ,0103 physical sciences ,0202 electrical engineering, electronic engineering, information engineering ,Fiber ,Irradiation ,Electrical and Electronic Engineering ,Instrumentation ,Power density ,business.industry ,Thermal conduction ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,Control and Systems Engineering ,Fuse (electrical) ,Optoelectronics ,business ,Order of magnitude ,Photonic-crystal fiber - Abstract
The unsteady-state thermal conduction process in several photonic crystal fibers (PCFs) was studied theoretically by the explicit finite-difference method using the thermochemical SiOx production model. The threshold power P th for fiber fuse propagation in these PCFs was one order of magnitude higher than that for conventional single-mode optical fibers (SMFs). These results agreed with the experimental results. P th of the triangular-lattice PCF was 69 W, and the resistance of this PCF to high-power irradiation was superior to that of SMF. The threshold power density for the honeycomb-structure PCF and/or triangular-lattice PCF was about 45 times larger than that of conventional SMFs. more...
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- 2021
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7. End Face Damage and Fiber Fuse Phenomena in Single-Mode Fiber-Optic Connectors
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Yoshito Shuto
- Subjects
Materials science ,Single-mode optical fiber ,020206 networking & telecommunications ,02 engineering and technology ,Thermal conduction ,01 natural sciences ,010309 optics ,Core (optical fiber) ,Cable gland ,0103 physical sciences ,0202 electrical engineering, electronic engineering, information engineering ,Reference surface ,Fuse (electrical) ,Fiber ,Laser power scaling ,Composite material - Abstract
The evolution of both the core melting and fiber fuse phenomena in a single-mode fiber-optic connector was studied theoretically. Carbon black was chosen as a light-absorbent material. A thin absorbent layer with a thickness of 1 μm order was assumed to be formed between the fiber end faces in the connector. When a high-power laser operating at 1.48 or 1.55 μm was input into the connector, the temperature on the fiber core surface increased owing to heat conduction from the light-absorbent material. The heat flow process of the core, which caused the core to melt or the fiber fuse phenomenon, was theoretically calculated with the explicit finite-difference method. The results indicated that initial attenuation of less than 0.5 dB was desirable to prevent core fusion in the connectors when the input 1.48 μm laser power was 1 W. It was found that a core temperature of more than 4000 K was necessary to generate and maintain a fiber fuse. more...
- Published
- 2016
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8. Heat Conduction Modeling of Fiber Fuse in Single-Mode Optical Fibers
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Yoshito Shuto
- Subjects
Core (optical fiber) ,Optical fiber ,Materials science ,law ,Fuse (electrical) ,Single-mode optical fiber ,Fiber ,Laser power scaling ,Composite material ,Thermal conduction ,Layer (electronics) ,law.invention - Abstract
The unsteady-state thermal conduction process in single-mode optical fiber was studied theoretically with the explicit finite-difference method. We assumed that the vitreous silica optical fiber underwent pyrolysis at elevated temperatures to form SiOx (x~1). We also proposed a model in which the optical absorption coefficient of the core layer increased with increasing molar concentration of SiOx. The core-center temperature changed suddenly and reached over 3×104 K when a 1.064-μm laser power of 2 W was input into a short core layer of 40 μm length, which was heated at 2923 K. This thermal wave, that is, a fiber fuse, increased in size and propagated toward the light source at a rate of about 0.54 m/s. The calculated propagation velocity of the fiber fuse was in agreement with the experimental value. Moreover, the average temperature of the radiated region of the core layer gradually approached a temperature of about 5700 K. It was found that the final average temperature was close to the experimentally reported values. more...
- Published
- 2014
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9. Cavity Pattern Formation and Its Dynamics of Fiber Fuse in Single-Mode Optical Fibers.
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Yoshito Shuto
- Subjects
SINGLE-mode optical fibers ,NONLINEAR oscillations ,NONLINEAR oscillators ,POPULATION dynamics ,PARAMETERS (Statistics) ,FIBER lasers - Abstract
The nonlinear oscillation model using the Van der Pol equation was able to phenomenologically explain the formation of periodic cavities, the cavity shape, and the regularity of the cavity pattern in the core layer as a result of the relaxation oscillation and cavity compression and/or deformation. We assumed the relationships between the parameters of the population dynamics of interacting self-oscillators using the Kuramoto model and the fiber fuse propagation, and found an equation describing the power dependence of the periodic cavity interval. The experimentally determined cavity intervals at P
th · P0 · 5W satisfied this equation. Furthermore, the experimental cavity intervals at P0 È 6W can be explained by considering the power dependence of the propagation velocity of the fiber fuse and the constant period of the Van der Pol oscillator. [ABSTRACT FROM AUTHOR] more...- Published
- 2020
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10. Simulation of Fiber Fuse Phenomenon in Single-Mode Optical Fibers
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Yoshito Shuto
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- 2015
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11. Fiber fuse phenomenon in triangular-profile single-mode optical fibers
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Ryo Nagase, Shuichi Yanagi, S. Asakawa, Yoshito Shuto, and Morio Kobayashi
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Optical fiber ,Materials science ,business.industry ,Single-mode optical fiber ,Physics::Optics ,Molecular physics ,Atomic and Molecular Physics, and Optics ,law.invention ,Core (optical fiber) ,Optics ,law ,Attenuation coefficient ,Dispersion (optics) ,Fiber ,Laser power scaling ,business ,Refractive index - Abstract
The unsteady-state thermal conduction processes in triangular-profile (TP) optical fibers, which exhibited zero chromatic dispersion near 1.55 /spl mu/m, were studied theoretically with the explicit finite-difference method (FDM). It was estimated that these fibers would exhibit a high-temperature optical absorption on the basis of the high-temperature loss-increase mechanism proposed for step-index (SI) optical fibers. The core-center temperature of the TP fibers changed suddenly and reached over 7/spl times/10/sup 5/ K when a 1.064-/spl mu/m laser power of 1 W was inputted into the core layer heated at 2608 K. This rapid heating of the core initiated the "fiber fuse" phenomenon. The propagation rates of the fiber fuse, estimated at 1.064 /spl mu/m, were in fairly good agreement with the experimentally determined values. It was found that the threshold powers for initiating the fiber fuse are linearly proportional to the roots of the effective core areas of both the SI and the TP optical fibers. This coincides the experimental result reported by Seo et al. more...
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- 2006
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12. Low-cost 10-gb/s optical receiver module using a novel plastic package and a passive alignment technique
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Endo Jun, Takeshi Kurosaki, Michiyuki Amano, Yasuhiro Suzuki, Kenji Yokoyama, Yoshito Shuto, Noboru Ishihara, T. Tadokoro, and M. Nakamura
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Materials science ,Preamplifier ,business.industry ,Bandwidth (signal processing) ,Electrical engineering ,Electronic packaging ,Biasing ,Atomic and Molecular Physics, and Optics ,Photodiode ,law.invention ,Gallium arsenide ,chemistry.chemical_compound ,Intermediate frequency ,chemistry ,law ,business ,Infrared microscopy - Abstract
A new low-cost 10-Gb/s optical receiver module constructed using a novel plastic package is proposed. Passive alignment using a glass V-groove substrate and an edge-illuminated refracting-facet photodiode (RFPD) was employed to reduce cost. Instead of a conventional GaAs IC, a Si-bipolar preamplifier IC was mounted on the package to reduce power consumption. High-speed signal lines with a bandwidth of more than 10 GHz were realized using a three-dimensional electromagnetic-field analysis. For the fabricated module, a 3-dB detection bandwidth of 7.7 GHz and a sensitivity of less than -14 dBm at 10 Gb/s were achieved. To confirm the reliability of the fabricated module, a damp-heat test without bias voltage and a temperature-cycling test were performed. The results show that the optical receiver module, if covered with silicone resin, has the ability to withstand humidity and thermal stress. more...
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- 2005
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13. Fiber fuse phenomenon in step-index single-mode optical fibers
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Ryo Nagase, Morio Kobayashi, Yoshito Shuto, S. Asakawa, and Shuichi Yanagi
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Materials science ,Optical fiber ,business.industry ,Single-mode optical fiber ,Condensed Matter Physics ,Thermal conduction ,Laser ,Atomic and Molecular Physics, and Optics ,law.invention ,Core (optical fiber) ,Thermal conductivity ,Optics ,law ,Fiber ,Laser power scaling ,Electrical and Electronic Engineering ,Atomic physics ,business - Abstract
The unsteady-state thermal conduction process in step-index single-mode (SM) optical fiber was studied theoretically with the explicit finite-difference method. We considered a high-temperature loss-increase mechanism, which includes two factors that bring about an increase in the absorption coefficients: 1) electronic conductivity due to the thermal ionization of a Ge-doped silica core and 2) thermochemical SiO production in silica glass. The core-center temperature changed suddenly and reached over 4/spl times/10/sup 5/ K when a 1.064-/spl mu/m laser power of 2 W was input into the core layer heated at 2723 K. This rapid heating of the core initiated the "fiber fuse" phenomenon. The high-temperature core areas were enlarged and propagated toward the light source. The propagation rates of the fiber fuse, estimated at 1.064 and 1.48 /spl mu/m, were in fair agreement with the experimentally determined values. We found that the threshold power for initiating the fiber fuse increases from 0.98 to 1.26 W when the input laser wavelength is increased from 1.06 to 1.55 /spl mu/m. more...
- Published
- 2004
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14. Simulation of fiber fuse phenomenon in single-mode optical fibers
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S. Asakawa, Kobayashi Masaru, Ryo Nagase, Yoshito Shuto, and Shuichi Yanagi
- Subjects
Optical fiber ,Materials science ,business.industry ,Infrared ,Single-mode optical fiber ,Optical power ,Thermal conduction ,Atomic and Molecular Physics, and Optics ,law.invention ,Core (optical fiber) ,Optics ,law ,Attenuation coefficient ,Fiber ,business - Abstract
The unsteady-state thermal conduction process in single-mode (SM) optical fiber was studied theoretically with the explicit finite-difference method (FDM). In the numerical calculation it was assumed that the electrical conductivity of the core layer increased rapidly above 1323 K. The core-center temperature changed suddenly and reached over 3/spl times/10/sup 5/ K when an optical power of 1 W was input into the core layer heated at 1373 K. This rapid heating of the core initiated the "fiber fuse" phenomenon. The high-temperature core areas, whose radiation spectrum extended over a wide range from the infrared to the ultraviolet regions, were enlarged and propagated toward the light source at a rate of about 0.7 m s/sup -1/. This rate was in fair agreement with the experimentally determined value. more...
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- 2003
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15. Generation mechanism on fiber fuse phenomenon in single-mode optical fibers
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Ryo Nagase, Shuichi Yanagi, Yoshito Shuto, and Shuichiro Asakawa
- Subjects
Mode volume ,Optical fiber ,Materials science ,Computer Networks and Communications ,business.industry ,Single-mode optical fiber ,General Physics and Astronomy ,Polarization-maintaining optical fiber ,Graded-index fiber ,law.invention ,Optics ,Normalized frequency (fiber optics) ,Double-clad fiber ,law ,Optoelectronics ,Electrical and Electronic Engineering ,Plastic optical fiber ,business - Abstract
Unsteady-state thermal conduction process in the single-mode (SM) optical fiber was theoretically studied with the explicit finite-difference method. In the numerical calculation it was assumed that the electrical conductivity of the core layer increased rapidly above 1050 °C. The core-center temperature changed suddenly and reached over ten thousand Kelvin when the optical power of 1 W was input to the core layer heated above 1000 °C. This rapid heating phenomenon also occurred when the optical power was reflected at the edge wall of the thermally produced cavity in the core layer. The occurrence of this phenomenon was restricted by the decrease in either the input optical power or the normalized frequency of the SM optical fiber. © 2003 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 86(11): 11–20, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.10150 more...
- Published
- 2003
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16. [Untitled]
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Yoshito Shuto
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Materials science ,Type (model theory) ,Topology ,Connection (mathematics) - Published
- 2002
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17. 光コネクタ用プラスチックフェルールの開発
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Hirotsugu Sato, Shuichi Yanagi, Yoshito Shuto, Shunichi Tohno, and Yuji Ueda
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- 2001
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18. [Untitled]
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Shunichi Tohno, Ueda Yuji, Yoshito Shuto, Shin Sumida, Shuichi Yanagi, and Hirotsugu Sato
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Materials science ,Ferrule ,Molding (process) ,Composite material - Published
- 2001
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19. [Untitled]
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Michiyuki AMANO, Shuichi YANAGI, Yoshito SHUTO, Hirotugu SATO, Shin SUMIDA, and Shun-ichi TOHNO
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Mechanical Engineering - Published
- 2000
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20. Plastic module of laser diode and photodiode mounted on planar lightwave circuit for access network
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F. Ichikawa, Shunichi Tohno, Y. Yamada, H. Sato, H. Toba, S. Kondo, M. Fukuda, J. Yoshida, T. Sugie, Yoshito Shuto, K. Suzuki, O. Suzuki, and Kuniharu Kato
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Materials science ,Laser diode ,business.industry ,Environmental tests ,Electronic packaging ,Biasing ,Temperature cycling ,Atomic and Molecular Physics, and Optics ,Semiconductor laser theory ,Photodiode ,law.invention ,law ,Optoelectronics ,business ,Diode - Abstract
Low-cost plastic packaging of laser diodes and photodiodes mounted on planar lightwave circuit (PLC) platform are developed and its reliability is confirmed under various environmental and endurance tests. The high performance of the module is maintained under reliability tests, such as high-humidity high-temperature tests (85/spl deg/C, 85%RH) and temperature cycling tests (-40/spl deg/C/85/spl deg/C). No laser diodes show any device characteristics change during environmental tests and their stability has very little dependence on current bias. Although the photodiodes show an increase in leakage current under high-temperature high-humidity tests and the rate of leakage current increase is proportional to the square root of bias voltage, the increase is negligible for system use. These plastic modules can be applied to actual access networks and other fiber-optic networks. more...
- Published
- 1999
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21. Optical characteristics of injection molded plastic ferrules for single-mode optical fiber applications
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S. Tohmo, Shuichi Yanagi, M. Ohno, Yoshito Shuto, and Hirotsugu Sato
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chemistry.chemical_classification ,Materials science ,media_common.quotation_subject ,Single-mode optical fiber ,Ferrule ,Polymer ,Replication (microscopy) ,Molding (process) ,medicine.disease_cause ,Atomic and Molecular Physics, and Optics ,chemistry ,Mold ,medicine ,Electrical and Electronic Engineering ,Eccentricity (behavior) ,Composite material ,Optical fiber connector ,media_common - Abstract
We injection molded a plastic ferrule for a single-mode optical fiber connector. We used liquid crystalline polymer (LCP) as the molding material because of its fine mold replication ability and introduced an eccentricity control mechanism into the ferrule mold. As a result, we succeeded in molding plastic ferrules whose eccentricity was less than 1 /spl mu/m by optimizing the eccentricity control conditions. The connection loss of these low eccentricity plastic ferrules was around 0.2 dB and they exhibited an excellent reflection characteristic of 52.5 dB. These initial results were maintained during mating tests and temperature and humidity cycling tests. more...
- Published
- 1999
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22. Optical characteristics and reliability of plastic split alignment sleeves for single-mode optical fiber connectors
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Shuichi Yanagi, M. Ohno, Hirotsugu Sato, Yoshito Shuto, and S. Tohno
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Materials science ,Optical fiber ,Glass-ceramic ,Single-mode optical fiber ,Thermosetting polymer ,Epoxy ,Durability ,Atomic and Molecular Physics, and Optics ,law.invention ,Vibration ,law ,visual_art ,visual_art.visual_art_medium ,Cubic zirconia ,Electrical and Electronic Engineering ,Composite material - Abstract
Split alignment sleeves for single-mode (SM) optical fiber connection are fabricated with a precise injection-molding technique using a thermosetting epoxy resin. The fabricated plastic sleeves exhibit dimensional accuracy of 50 dB. The plastic sleeves exhibit good resistance in 500-cycle mating tests using zirconia and/or glass ceramic ferrules, and in vibration and impact tests as well. The initial optical characteristics are maintained in both short-term and long-term environmental durability tests. more...
- Published
- 1999
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23. Quadratic hyperpolarizabilities of nitro-substituted pseudo-linear dye molecules with ethylenic and azo bridges
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Yoshito Shuto
- Subjects
Quadratic equation ,Materials science ,Polymer chemistry ,Nitro ,Molecule ,Physical and Theoretical Chemistry ,Condensed Matter Physics ,Atomic and Molecular Physics, and Optics - Published
- 1998
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24. Optical, thermal-strain, and water-sorption properties of plastic resins for laser-diode molding
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Shunichi Tohno, Hirotsugu Sato, Mitsuo Fukuda, and Yoshito Shuto
- Subjects
Materials science ,Laser diode ,Computer Networks and Communications ,law ,General Physics and Astronomy ,Thermal strain ,Water sorption ,Molding (process) ,Electrical and Electronic Engineering ,Composite material ,law.invention - Published
- 1998
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25. Vertically stacked coupler and serially grafted waveguide: Hybrid waveguide structures formed using an electro-optic polymer
- Author
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Michiyuki Amano, Toshio Watanabe, Satoru Tomaru, Makoto Hikita, and Yoshito Shuto
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chemistry.chemical_classification ,Materials science ,business.industry ,Butt coupling ,Physics::Optics ,General Physics and Astronomy ,Polymer ,Waveguide (optics) ,law.invention ,Directional coupling ,Optics ,chemistry ,law ,Optical intensity ,Optoelectronics ,Reactive-ion etching ,Photolithography ,business ,Nonlinear Sciences::Pattern Formation and Solitons ,Refractive index - Abstract
Two hybrid waveguide structures formed using an electro-optic polymer are described. They are a vertically stacked coupler and a serially grafted waveguide. These structures were fabricated by spin-coating, photolithographic, and reactive ion etching processes. Directional coupling was successfully demonstrated between the vertically stacked waveguides, and the crosstalk was −15 dB. This waveguide structure was applied to an optical intensity modulator. The serially grafted waveguide allows butt coupling between the functional waveguide and passive waveguides, and the connection loss at a grafting point was as low as 0.005 dB. This waveguide structure was applied to a Mach–Zehnder optical intensity modulator and a quasi-phase-matched second-harmonic generator. more...
- Published
- 1998
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26. Quasi-phase-matched second-harmonic generation in diazo-dye-substituted polymer channel waveguides
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Yoshito Shuto, Michiyuki Amano, Toshio Watanabe, Itaru Yokohama, Makoto Hikita, and Satoru Tomaru
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Materials science ,business.industry ,Energy conversion efficiency ,Phase (waves) ,Physics::Optics ,Nonlinear optics ,Second-harmonic generation ,Grating ,Condensed Matter Physics ,Atomic and Molecular Physics, and Optics ,law.invention ,Optics ,law ,Electrical and Electronic Engineering ,Reactive-ion etching ,business ,Waveguide ,Diffraction grating - Abstract
First-order quasi-phase-matched (QPM) second-harmonic generation (SHG) is demonstrated in a poled diazo-dye-substituted polymer channel waveguide. The channel waveguide with a nonlinear grating was fabricated by the serial grafting technique using conventional photolithography and reactive ion etching. The dependence of the conversion efficiency on both the waveguide parameter and the grating structure was derived theoretically. A normalized internal conversion efficiency of 1.1% W/sup -1/ cm/sup -2/ at 1.586 /spl mu/m was obtained in the fabricated waveguide with a phase-matched interaction length of 3.4 mm. The experimentally obtained conversion efficiency is compared with the theoretical value, taking into account the effect of mode-mismatching and propagation loss. more...
- Published
- 1997
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27. Evaluation of High-Temperature Absorption Coefficients of Optical Fibers
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Shuichi Yanagi, Ryo Nagase, Yoshito Shuto, Morio Kobayashi, and S. Asakawa
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Optical fiber ,Materials science ,Single-mode optical fiber ,Analytical chemistry ,Thermal ionization ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,law.invention ,Core (optical fiber) ,law ,Electrical resistivity and conductivity ,Attenuation coefficient ,Fiber ,Electrical and Electronic Engineering ,Absorption (chemistry) - Abstract
The large absorption coefficient /spl alpha/ of single-mode optical fiber at high temperatures is closely related to the generation of the fiber fuse phenomenon. We propose a high-temperature loss-increase mechanism, which includes three factors that bring about an increase in the /spl alpha/ values: 1) point-defect (Ge E' center) formation; 2) electronic conductivity due to the thermal ionization of a Ge-doped silica core; and 3) thermochemical SiO production in the silica glass. Ge E'-center formation and electronic conductivity in the Ge-doped silica core are dominant factors at temperatures near the critical temperature of 1323 K. However, these factors cannot explain the large /spl alpha/ values observed at high temperatures above 2273 K. By contrast, SiO gas and/or solid, which are thermochemically produced in the silica glass, exhibit large /spl alpha/ values of the order of 10/sup 4/ m/sup -1/ at 2293 K. The /spl alpha/ value estimated at 0.5 /spl mu/m is close to the experimental value reported in the fiber fuse experiments. more...
- Published
- 2004
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28. Fiber Fuse Generation in Single-Mode Fiber-Optic Connectors
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S. Asakawa, Yoshito Shuto, Shuichi Yanagi, Morio Kobayashi, and Ryo Nagase
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Materials science ,Optical fiber ,business.industry ,Single-mode optical fiber ,Ferrule ,Optical power ,Laser ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,law.invention ,Optics ,law ,Attenuation coefficient ,Fiber ,Electrical and Electronic Engineering ,Composite material ,Air gap (plumbing) ,business - Abstract
The evolution of the fiber fuse phenomenon in a single-mode fiber-optic connector was studied theoretically. A narrow air gap of the order of 1 /spl mu/m was assumed to be formed between the fiber end-faces in the connector as a result of the adhesion of dust to both the ferrule and the fiber end-faces. It was assumed that there was a thin water layer in the gap because condensable water molecules in the air could easily be trapped by the SiOH groups on the silica-glass surface. The water layer exhibited a large absorption coefficient of about 850 cm/sup -1/ at 1.48 /spl mu/m. The temperature distributions near the air gap were numerically calculated by using the explicit finite-difference method. When a high-power laser operating at 1.48 /spl mu/m was input into the connector, the temperature along the fiber-core center increased abruptly at the thin water layer. The air gap was heated above 4/spl times/10/sup 5/ K when the optical power was 2 W and the gap was 1 /spl mu/m. The heat in the air gap gradually diffused into the neighboring optical fiber over time. The temperature of the heated fiber reached over 1/spl times/10/sup 4/ K, which is high enough to initiate the fiber fuse phenomenon. more...
- Published
- 2004
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29. Reflection measurement technique of electro‐optic coefficients in lithium niobate crystals and poled polymer films
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Yoshito Shuto and Michiyuki Amano
- Subjects
chemistry.chemical_classification ,Materials science ,business.industry ,Lithium niobate ,General Physics and Astronomy ,Polymer ,Piezoelectricity ,Pockels effect ,Optical reflection ,chemistry.chemical_compound ,Optics ,Reflection (mathematics) ,Lithium niobate crystal ,chemistry ,Optoelectronics ,business ,Phase modulation - Abstract
A simple reflection technique proposed by Teng and Man [Appl. Phys. Lett. 56, 1734 (1990)] as well as independently by Schildkraut [Appl. Opt. 29, 2839 (1990)] for measuring the electro‐optic coefficients of poled polymer films is applied to measure the r33 values of both z‐cut lithium niobate crystal and diazo‐dye‐substituted polymer films. The measured r33 value of the lithium niobate crystal is in excellent agreement with the known value, and the observed r33 values of the poled polymer films agree well with those predicted from the second‐harmonic‐generation measurements. more...
- Published
- 1995
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30. Plastic split alignment sleeves for single-mode fiber connection of MU- and SC-type ferrules
- Author
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Shunichi Tohno, Hirotsugu Sato, M. Ohno, Shuichi Yanagi, Michiyuki Amano, Shin Sumida, Yoshito Shuto, and S. Iwano
- Subjects
Optical fiber ,Fabrication ,Materials science ,Single-mode optical fiber ,Optical polymers ,Thermosetting polymer ,Epoxy ,Optical coupling ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,law.invention ,law ,visual_art ,Return loss ,visual_art.visual_art_medium ,Forensic engineering ,Electrical and Electronic Engineering ,Composite material - Abstract
Split alignment sleeves for the single-mode optical-fiber connection of MU and SC-type ferrules were successfully fabricated for the first time with a precise injection-molding technique using a thermosetting epoxy resin. The optimum inner radii of the plastic sleeves were determined with a view to realizing both suitable gauge retention forces for the ferrules and a small fiber offset of 1 /spl mu/m between them. The adapters incorporating the plastic sleeves showed excellent performance with an average connection loss of 0.09 dB and a return loss of >50 dB. more...
- Published
- 2001
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31. Electrooptic light modulation and second-harmonic generation in novel diazo-dye-substituted poled polymers
- Author
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Toshikuni Kaino, Michiyuki Amano, and Yoshito Shuto
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chemistry.chemical_classification ,Materials science ,business.industry ,Second-harmonic generation ,Polymer ,Methacrylate ,Electro-optics ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,chemistry.chemical_compound ,chemistry ,Electric field ,Optoelectronics ,Thermal stability ,Polymer blend ,Electrical and Electronic Engineering ,Methyl methacrylate ,business - Abstract
The nonlinear-optical susceptibilities, x/sup (2)/, of a diazo-dye-substituted polymer poled with high electric fields were determined experimentally and theoretically. The electrooptic modulation of He-Ne laser light in a traveling-wave channel-waveguide modulator using the diazo-dye-substituted poled polymer is reported, and the linear electrooptic coefficient of the poled polymer is estimated from a measured half-wave voltage. The polymer studied is a poly(methyl methacrylate) copolymerized with a methacrylate ester of the dicyanovinyl-terminated diazo dye derivative. This polymer is called 3RDCVXY. The corona-poled 3RDCVXY polymer exhibits a x/sup (2)/ value of 1*10/sup -6/ esu at 1.06 mu m. The thermal stability is excellent even at 80 degrees C. The poled 3RDCVXY polymer film shows a linear electrooptic coefficient as high as 40 pm/V at 0.633 mu m. An electrooptical light modulation in the channel 3RDCVXY polymer waveguides with a half-wave voltage as low as 5 V was obtained. > more...
- Published
- 1991
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32. Quasi‐phase‐matched second harmonic generation in a polymer waveguide with a periodic poled structure
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Itaru Yokohoma, Toshikuni Kaino, Yoshito Shuto, Masaki Asobe, Michiyuki Amano, Satoru Tomaru, Makoto Hikita, and Toshio Watanabe
- Subjects
Materials science ,Fabrication ,Physics and Astronomy (miscellaneous) ,business.industry ,Phase (waves) ,Second-harmonic generation ,Polarization (waves) ,law.invention ,Wavelength ,Optics ,law ,Reactive-ion etching ,Photolithography ,business ,Waveguide - Abstract
Quasi‐phase‐matched (QPM) second harmonic generation in a poled polymer waveguide has been realized. A waveguide with a periodic structure was fabricated by conventional photolithography and reactive ion etching. The waveguide with a QPM structure was composed of poled polymer and UV cured epoxy resin. Phase‐matched second harmonic generation was observed, using laser light with a fundamental wavelength 1.48–1.65 μm. This phase matched condition was dependent on the periodic length. The waveguide had a typical second harmonic generation efficiency of about 4×10−1% W−1 cm−2 around a wavelength of 1.55 μm. more...
- Published
- 1996
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33. Fiber fuse terminator
- Author
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Yoshito Shuto, S. Asakawa, Ryo Nagase, Shuichi Yanagi, and Morio Kobayashi
- Subjects
Multi-mode optical fiber ,genetic structures ,business.industry ,Computer science ,Electrical engineering ,Polarization-maintaining optical fiber ,Graded-index fiber ,eye diseases ,Fiber-optic communication ,Fiber optic sensor ,Fiber optic splitter ,Optoelectronics ,Dispersion-shifted fiber ,sense organs ,business ,Plastic optical fiber - Abstract
We developed a fiber fuse terminator to ensure the safe operation of high power optical network systems. The performance of this fiber fuse terminator was satisfactory as regards an optical input of 2 W. more...
- Published
- 2004
- Full Text
- View/download PDF
34. A bidirectional single fiber 1.25 Gb/s optical transceiver module with SFP package using PLC
- Author
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A. Kinda, M. Ishii, Masahiro Yanagisawa, R. Kasaliara, T. Kilagawa, Y. Suzuki, I. Ogawa, S. Mino, A. Obki, Yoshito Shuto, Toshikazu Hashimoto, and R. Nagase
- Subjects
Computer science ,business.industry ,Optical cross-connect ,Optical modulation amplitude ,Passive optical network ,law.invention ,law ,Fiber optic splitter ,Electronic engineering ,Transceiver ,business ,Plastic optical fiber ,Optical add-drop multiplexer ,Optical attenuator ,Computer hardware - Published
- 2004
- Full Text
- View/download PDF
35. Novel ‘‘serially grafted’’ connection between functional and passive polymer waveguides
- Author
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Satoru Tomaru, Michiyuki Amano, Toshio Watanabe, Makoto Hikita, and Yoshito Shuto
- Subjects
chemistry.chemical_classification ,Quantitative Biology::Biomolecules ,Fabrication ,Materials science ,genetic structures ,Physics and Astronomy (miscellaneous) ,business.industry ,Physics::Optics ,Polymer ,Mach–Zehnder interferometer ,eye diseases ,Connection (mathematics) ,Condensed Matter::Soft Condensed Matter ,Optics ,Optical modulator ,chemistry ,Modulation ,Optical intensity ,Optoelectronics ,sense organs ,business ,Polymer waveguide ,Nonlinear Sciences::Pattern Formation and Solitons - Abstract
A serially grafted connection between polymer waveguides is realized. This technique allows a passive polymer waveguide to be connected to a functional polymer waveguide with a connection loss of 0.005 dB. It is also applied to a Mach–Zehnder modulator using an electro‐optic polymer, and optical intensity modulation in the serially grafted modulator is successfully demonstrated. more...
- Published
- 1994
- Full Text
- View/download PDF
36. Injection molded fiber-optic connector components for single-mode applications
- Author
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Yoshito Shuto, Shuichi Yanagi, M. Ohno, Hirotsugu Sato, and S. Tohno
- Subjects
Cable gland ,Engineering drawing ,Injection molding process ,Optical fiber ,Materials science ,law ,Single-mode optical fiber ,Thermal stability ,Composite material ,Hot and humid ,law.invention - Abstract
Plastic ferrules and split alignment sleeves for single-mode fiber-optic connectors were successfully fabricated by an injection molding process. The optical characteristics of these plastic components are compatible with single-mode SC-type connectors and they are also stable under hot and humid conditions. more...
- Published
- 2002
- Full Text
- View/download PDF
37. Optical intensity modulation in a vertically stacked coupler incorporating electro‐optic polymer
- Author
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Haruki Kozawaguchi, Michiyuki Amano, Satoru Tomaru, Ryoko Yoshimura, Makoto Hikita, and Yoshito Shuto
- Subjects
Spin coating ,Materials science ,Fabrication ,Physics and Astronomy (miscellaneous) ,business.industry ,Cladding (fiber optics) ,law.invention ,Optics ,Optical modulator ,law ,Power dividers and directional couplers ,Reactive-ion etching ,Photolithography ,business ,Intensity modulation - Abstract
A vertically stacked directional coupler incorporating electro‐optic poled polymer was fabricated by spin coating, photolithography, and reactive ion etching processes, based on the fabrication technique used for polymeric single‐mode channel waveguides. Vertically coupled operation at 1.3 μm have been achieved between two stacked channels which were kept 3.5–5 μm apart by a narrow cladding layer. The intensity modulation has been clearly demonstrated in the coupler with electrodes when a voltage is applied at 10 kHz between them. more...
- Published
- 1993
- Full Text
- View/download PDF
38. Organic patch sensor for electro-optic measurement of electrical signals in integrated circuits
- Author
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Michiyuki Amano, Tadao Nagatsuma, Yoshito Shuto, Makoto Yaita, and Mitsuru Shinagawa
- Subjects
Materials science ,business.industry ,Detector ,Integrated circuit ,engineering.material ,Electro-optics ,law.invention ,Optics ,Coating ,law ,Measuring instrument ,engineering ,Optoelectronics ,Electrical and Electronic Engineering ,Thin film ,business ,Sensitivity (electronics) ,Voltage - Abstract
A highly sensitive, versatile and low-cost electric field sensor has been developed for measuring internal electrical signals in integrated circuits using an electro-optic sampling technique. This sensor uses an organic nonlinear optical (NLO) polymer coated on thin polyamide films and is directly bonded to the circuit under test without a mirror coating. Electro-optic sampling was conducted using the sensor, and a voltage sensitivity of less than a few tens of millivolts was obtained. more...
- Published
- 1991
- Full Text
- View/download PDF
39. Diazo dye attached electro-optical polymer and its applications to waveguide devices and electro-optical sampling
- Author
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Tadao Nagatsuma, Makoto Yaita, Michiyuki Amano, Yoshito Shuto, Toshio Watanabe, Satoru Tomaru, and Makoto Hikita
- Subjects
chemistry.chemical_classification ,Materials science ,business.industry ,Polymer ,Chromophore ,law.invention ,Optical modulator ,Optics ,chemistry ,law ,Electric field ,Power dividers and directional couplers ,Reactive-ion etching ,Absorption (electromagnetic radiation) ,business ,Waveguide - Abstract
An electro-optical polymer was synthesized where a diazo dye with a dicyanovinyl group as an electron acceptor and a diethylamino group as a donor is attached to the polymer chain. The electro-optical coefficient (r) reached 30 pm/V. It was found that the edge absorption of the chromophore caused a loss increase in the near infrared region, which indicates that the increase in the r value leads to a propagation loss increase in the material. The loss is around 1.0 dB/cm in a single-mode waveguide fabricated by using oxygen reactive ion etching. The polymer waveguide is applied to two types of devices, a Mach-Zehnder optical modulator and a vertically stacked directional coupler, which both achieve electro-optical modulation. As another application, electro-optical measurement of an electric field in a high-speed circuit device is demonstrated, where the polymer is processed into a chip film probe and patched to an integrated circuit, thus enabling the electric signal to be detected. more...
- Published
- 1994
- Full Text
- View/download PDF
40. Nonlinear optical properties of chromophore-functionalized polymeric materials
- Author
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Toshikuni Kaino, Yoshito Shuto, and Michiyuki Amano
- Subjects
chemistry.chemical_classification ,Dipole ,Wavelength ,Fabrication ,Materials science ,chemistry ,Polymer chemistry ,Copolymer ,Analytical chemistry ,Thermal stability ,Polymer ,Chromophore ,Waveguide (optics) - Abstract
Nonlinear optical (NLO) properties of chromophore-functionalized polymeric materials (dye-attached sid echain polymers and dye-introduced main chain polymers) are discussed. These polymers show promise for use in NLO devices because of their processability, transparency and thermal stability. A dicyanovinyl-terminated methyl-substituted diazo dye-attached methacrylate copolymer (3RDCVXY), which is newly synthesized by the authors, is investigated for its second and third-order NLO properties. The βμg (β: second-order nonlinear optical molecular susceptibility, μg:dipole moment) value of 3RDCVXY is greater than that of a previously reported nitro-substituted diazo dye (3RNO2) and a monoazo dye (2RNO2) from 1-06 to 1-70 μm wavelengths. The methyl-substitution is effective for increasing the dye content in the copolymer and as a result the content of the 3RDCVXY dye is nearly 2 times larger than that of the 3RNO2 dye. The second-order nonlinear optical coefficient (χ(2)) measurement of the polymers as a function of fundamental wavelength reveals that the maximum χ(2) of 3RDCVXY reaches 1.0 × 10−6 esu, which is larger than those of 3RNO2 and LiNbO3 by 3 and 7 times, respectively. A thermal aging test shows that the χ(2) of 3RDCVXY is stable even at 80°C for more than 6 months. 3RDCVXY can, therefore be, used as a material for optical devices. A traveling wave phase modulator is fabricated using 3RDCVXY. To date a half wave voltage of 5V has been obtained for a 15 mm channel waveguide with an r33 of 40 pm/V at 633 nm, which is larger than that of a LiNbO3. From the χ(2) value, a half voltage of less than 2V is possible by refining the modulator fabrication process. An application as a highly sensitive electric field sensor for internal electrical signal measurement in ICs is also discussed. The third-order nonlinear optical coefficient (χ(3)) of 3RDCVXY reaches 5 × 10−11 esu at the near resonant region. This value is almost the same as that of 3RNO2. With polymers where the dye molecules are introduced into the polymer backbone (a main chain polymer), a χ(3) larger than 10−11 esu is obtained even in a monoazo dye introduced polymer. From this point of view, main chain polymers are promising for the development of large χ(3) processable material. more...
- Published
- 1992
- Full Text
- View/download PDF
41. Electro-optical light modulation in novel azo-dye-substituted poled polymers
- Author
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Toshikuni Kaino, Michiyuki Amano, and Yoshito Shuto
- Subjects
chemistry.chemical_classification ,Materials science ,business.industry ,Poling ,Intermolecular force ,Hyperpolarizability ,Polymer ,chemistry.chemical_compound ,symbols.namesake ,Optics ,chemistry ,Electroactive polymers ,symbols ,Physical chemistry ,Diazo ,Thermal stability ,van der Waals force ,business - Abstract
We present results on nonlinear optical properties of newly-synthesized diazo-dye-substituted methacrylate polymers. These dye-substituted polymers, which have been developed for EO devices, contain a dicyanovinyl-terminated, dimethyl-substituted diazo (3RDCVXY) dye exhibiting a larger hyperpolarizability (beta) than that of nitro-terminated diazo (3RN) or monoazo dye. In order to describe the relationship between a bulk susceptibility (chi) (2) and the (beta) value in the presence of electric poling field, a molecular statistical model is proposed. In the model the intermolecular potential due to the van der Waals forces in transitory aggregates is considered. As the 3RDCVXY dyes, which have the central benzene ring substituted by methyl groups, are prevented to come close to each other, the intermolecular interactions influence more weakly on the 3RDCVXY polymers than the 3RN polymers. As a result, the corona-poled 3RDCVXY polymer exhibits a large (chi) (2) value of 1 X 10-6 esu at 1.06 micrometers , whose thermal stability is excellent even at 80 degree(s)C. The poled 3RDCVXY polymer film exhibits a linear EO coefficient as high as 40 pm/V at 0.633 micrometers . An electro-optical light modulation in the channel 3RDCVXY polymer waveguides with half-wave voltage as low as 5 V is also presented. more...
- Published
- 1991
- Full Text
- View/download PDF
42. A picosecond optical-Kerr-shutter switch using an organic solution in a capillary waveguide
- Author
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Hideki Kobayashi, Hirohisa Kanbara, Ken'ichi Kubodera, and Yoshito Shuto
- Abstract
Optically-controlled optical switches will be key elements in time-division multiplexing devices for future optical communication and computing systems. Glass fibers have been applied to such switches1 utilizing easy fabrication of long interaction length and small core diameter in fibers, however, their optical nonlinearities are quite small. Organic nonlinear optical materials have been applied to efficient optical switches.2,3 In this paper, an even more efficient, high-speed optical- Kerr-shutter switch is demonstrated using a recently-synthesized organic material, 4-(N,N-diethylamino)-β-nitrostyrene (DEANST),4 which has large third-order susceptibility x(3) and high solubility. more...
- Published
- 1991
- Full Text
- View/download PDF
43. A Novel Injection-Molded Precision Plastic Platform for the Passive Alignment of a Polymer Waveguide Film and Optical Fibers
- Author
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Michiyuki Amano, Shunichi Tohno, Saburo Imamura, Hirotsugu Sato, Satoru Tomaru, Yasuaki Tamura, Yoshito Shuto, and Makoto Hikita
- Subjects
chemistry.chemical_classification ,Optical fiber ,Materials science ,business.industry ,Connection (vector bundle) ,General Engineering ,Physics::Optics ,General Physics and Astronomy ,Port (circuit theory) ,Polymer ,Molding (process) ,law.invention ,Core (optical fiber) ,Optics ,chemistry ,law ,Polymer waveguide ,business - Abstract
A newly-designed plastic alignment platform formed by a precise injection molding technique is proposed for connecting a polymer waveguide film to optical fibers. This platform consists of a pair of parallel arrayed V-grooves separated by a flat cavity for the polymer waveguide film. The core positions of the film are strictly determined by using polymer processing techniques including microlithography. A precisely aligned connection is then realized simply by placing the polymer waveguide in the mount cavity of the component. This provides an average connection loss of 0.2 dB/port. more...
- Published
- 1998
- Full Text
- View/download PDF
44. Injection moulded optical alignment sleeve for singlemode connection
- Author
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Hirotsugu Sato, Yasuaki Tamura, M. Ohno, Shuichi Yanagi, Shunichi Tohno, and Yoshito Shuto
- Subjects
Engineering drawing ,Optical alignment ,Materials science ,Connection (principal bundle) ,Thermosetting polymer ,Injection moulding ,Electrical and Electronic Engineering ,Composite material - Abstract
Plastic optical alignment sleeves for singlemode connection were successfully fabricated by the thermoset injection moulding process. The split sleeves exhibit excellent dimensional accuracy (± 2 µm) and have extremely smooth surfaces (Ra < 0.1 µm). They are compatible with SC-type connectors and the average optical loss is < 0.1 dB for singlemode SC plugs. more...
- Published
- 1998
- Full Text
- View/download PDF
45. Relaxation process for second-order nonlinear optical properties of poled diazo-dye-substituted polymers
- Author
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Yoshito Shuto and Michiyuki Amano
- Subjects
chemistry.chemical_classification ,Arrhenius equation ,Materials science ,business.industry ,Relaxation (NMR) ,General Physics and Astronomy ,Nonlinear optics ,Thermodynamics ,Polymer ,Activation energy ,Pockels effect ,symbols.namesake ,Optics ,chemistry ,symbols ,Glass transition ,business ,Cole–Cole equation - Abstract
This paper describes the transient properties of the second‐order nonlinear optical processes of a diazo‐dye‐substituted poled polymer. The temperature dependences of bulk susceptibilities and Pockels coefficients are measured below the glass transition temperature to estimate relaxation times. The activation energy of 43 kcal/mol determined from the Arrhenius plots of the relaxation times is assigned to that of the α relaxation of the diazo‐dye‐substituted polymer. The relaxation of the induced alignment of diazo‐dye side groups is restricted because of both the large dye molecular volume of greater than 500 A3 and the very small cumulative distribution of local free volumes which are greater than the dye molecular volume in the polymer. more...
- Published
- 1996
- Full Text
- View/download PDF
46. Normal-mode analysis of noncollinearly phase-matched second-harmonic generation in poled-polymer thin-film waveguides
- Author
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Yoshito Shuto
- Subjects
Total internal reflection ,Materials science ,business.industry ,Phase (waves) ,Second-harmonic imaging microscopy ,Physics::Optics ,Nonlinear optics ,Second-harmonic generation ,Statistical and Nonlinear Physics ,Atomic and Molecular Physics, and Optics ,law.invention ,Semiconductor laser theory ,Condensed Matter::Materials Science ,Optics ,law ,Normal mode ,business ,Waveguide - Abstract
Noncollinearly phase-matched second-harmonic generation (SHG) in a thin-film waveguide has been analyzed by the normal-mode analysis technique. When the waveguide film is composed of a poled polymer, three non-collinear SHG processes are possible. For each process a simple formula for SHG efficiency is given in terms of waveguide and nonlinear-optical parameters. Computational examples are plotted for the waveguide film of stilbene-dye-substituted methacrylate polymer on a glass substrate. The calculated matching angle and efficiency agree fairly well with the measured values. The analysis shows that the efficiency can be increased as much as 1%/W when we use the TM0ω-TM12ω process and that the introduction of a channel-waveguide geometry is effective in increasing the efficiencies. more...
- Published
- 1993
- Full Text
- View/download PDF
47. Electrooptic Light Modulation in Poled Azo-Dye-Substituted Polymer Waveguides
- Author
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Michiyuki Amano, Toshikuni Kaino, and Yoshito Shuto
- Subjects
chemistry.chemical_classification ,Materials science ,business.industry ,General Engineering ,General Physics and Astronomy ,Polymer ,Waveguide (optics) ,Light modulation ,Optics ,chemistry ,Modulation ,Side chain ,Copolymer ,Thin film ,business ,Polymer waveguide - Abstract
The DC electrooptic modulation of 0.633-µm He-Ne laser light has been measured in thin-film waveguides of copolymers containing Disperse Red-1 (DR1) and/or novel dis-azo-dye side chains. The polarized laser light is butt-coupled to the polymer waveguides with propagation length of 4 mm and film thickness of 10-15 µm. The DC linear electrooptic coefficients r33 of the poled DR1- and dis-azo-dye-substituted polymer films are estimated to be 18 pm/V and 27 pm/V at 0.633 µm. Comparison with second-harmonic generation results demonstrates that the DC linear electrooptic effect in the poled azo-dye-substituted polymers is primarily electronic in nature. more...
- Published
- 1991
- Full Text
- View/download PDF
48. High-temperature stability of optical transmission properties attained by liquid-crystal polymer jacket
- Author
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F. Yamamoto, Y. Takeuchi, and Yoshito Shuto
- Subjects
chemistry.chemical_classification ,Optical fiber ,Materials science ,business.industry ,Capacitive sensing ,Polymer ,Atmospheric temperature range ,Atomic and Molecular Physics, and Optics ,Thermal expansion ,law.invention ,Polyester ,Optics ,chemistry ,law ,Liquid crystal ,Thermal ,Composite material ,business - Abstract
Liquid crystal polyester (LCP) tight jackets, developed as secondary coatings on optical fibers, exhibit Young's moduli of 10-20 GPa and linear expansion coefficients on the order of 10-6/°C. Because of their low linear expansion coefficients, and because they exhibit no thermal shrinkage, the LCP jackets cause a slight change in fiber strain on the order of 10-4percent/°C, or a change in the thermal coefficients of the transit time delay as low as 14-29 ps/km°C in an 80 to -60°C temperature range for tight-jacketed optical fibers. Furthermore, the LCP tight-jacketed optical fibers exhibit no excess loss in this temperature range. more...
- Published
- 1986
- Full Text
- View/download PDF
49. High Strength, Low Thermal Expansion Coefficient Tight-Jacketed Optical Fiber with Thermotropic Liquid Crystal Polymer
- Author
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Yoshito Shuto and F. Yamamoto
- Subjects
Materials science ,Optical fiber ,law ,General Materials Science ,General Chemistry ,Composite material ,Condensed Matter Physics ,Thermotropic crystal ,Thermal expansion ,law.invention - Published
- 1989
- Full Text
- View/download PDF
50. High-modulus low-linear-expansion-coefficient loose-jacket optical fibers
- Author
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S. Yamakawa, Yoshito Shuto, F. Yamamoto, and H. Itoh
- Subjects
All-silica fiber ,Materials science ,Physics::Optics ,Polarization-maintaining optical fiber ,Microstructured optical fiber ,Fiber ,Composite material ,Plastic optical fiber ,Hard-clad silica optical fiber ,Atomic and Molecular Physics, and Optics ,Thermal expansion ,Photonic-crystal fiber - Abstract
Optical fibers loosely jacketed with high-modulus low-linear-expansion-coefficient polymers have been proposed, and the mechanical, thermal, and optical properties have been investigated. The loose-jacket tube is made of highly oriented polyoxymethylene (POM), which is produced by tensile-drawing the isotropic POM tube with dielectric heating. The oriented POM exhibits Young's moduli 20-40 GPa and linear expansion coefficients of the order of 10^{-5}-10^{-6}\deg C-1. Owing to the low linear expansion coefficients of the material, the oriented POM loose-jacket optical fiber has no low-temperature excess losses, which is due to fiber bends caused by thermal contraction of the loose tube, in the -60-80\deg C temperature range. more...
- Published
- 1984
- Full Text
- View/download PDF
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