Browsing by Author "Lin, Shiuan-Huei"

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An Efficient Solar Concentrator using Volume hologram
(2011)
Hsieh, Mei-Li
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Lin, Shiuan-Huei
;
Hsu, Ken Y.
;
Burr, Jim A.
;
Lin, Shawn-Yu
In this paper, we propose a simple technique to realize a compact and nearly all-angle solar energy concentrator using a volume holographic element (VHE). Our theoretical calculation predicts up to a fivefold concentration of energy per unit area of photovoltaic material. Hence, our holographic approach can offer an exceedingly high solar-concentration, a universal solution that can be easily integrated to any solar cells. Both the analysis and design of the volume holographic element will be described and demonstrated.
Analysis of a lens-array modulated coaxial holographic data storage system with considering recording dynamics of material
(2017-09-18)
Yu, Yeh-Wei
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Yang, Chi-Hsiang
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Yang, Tsung-Hsun
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Lin, Shiuan-Huei
;
Sun, Ching-Cherng
In the first time, a simulation model with considering the recording dynamics of material is built and is used to simulate evolution of the grating strength of the recorded hologram in a coaxial volume holographic memory system. In addition, phase modulation by lens array in the reference is introduced and observed to perform better diffracted signal quality and higher shifting selectivity, in both simulation and experiment. The use of lens array is found to provide multiple advantages in volume holographic memory system. The new simulation model potentially can be used to precisely design the system to obtain higher diffracted signal quality, higher shifting selectivity, and reduction of M# consumption and increase of storage capacity. (C) 2017 Optical Society of America
Chemical vapor deposition growth of bilayer graphene via altering gas flux geometry
(2019-11-30)
Petrov, Stefan
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Rafailov, Peter M.
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Marinova, Vera
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Lin, Shiuan-Huei
;
Lai, Yi-Chun
Graphene films with high content of bilayer graphene are obtained by chemical vapor deposition technique on copper (Cu) foil by means of suitably designing the flux geometries of the reactant gases. First single-layer graphene growth is optimized using a preliminary oxygen passivation of the Cu substrate which facilitates the formation of larger graphene grains with low defect density. Then, in order to enhance the transport of reactant species to the catalyst substrate, the gas flux geometry is modified in two ways: (i) fixing a graphite holder next to the Cu substrate perpendicular to the stream of the flux gases or (ii) positioning the Cu foil into a graphite shelter. It is found that both modifications facilitate the growth of a second graphene layer leading to increased formation of bilayer graphene. The obtained graphene layers are characterized by Raman spectroscopy (with special focus on the overtone (2D) of the disorder-induced band), scanning electron microscopy, transmission electron microscopy, atomic force microscope analysis and optical transmission measurements. Narrow symmetric 2D Raman peaks with linewidths ranging down to 22 cm(-1) but blue-shifted with respect to that of single-layer graphene are obtained from graphite holder- and shelter-grown samples indicating high-quality bilayer graphene.
Co-doping with polysquaraine enhances the holographic optical data storage of PMMA/PQ photopolymers
(2011)
Ko, Cheng-Jung
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Chang, Yeh-Lu
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Hsiao, Yi-Nan
;
Chen, Po-Lin
;
Lin, Shiuan-Huei
In this study, we synthesised poly(3-octylpyrrole-co-squaric acid) (PSQ3), a polysquaraine, through the reaction of 3-octylpyrrole and squaric acid, and then co-doped it with phenanthrenequinone (PQ) into poly(methyl methacrylate) (PMMA) to improve the holographic data storage characteristics of the photopolymer. The photopolymers co-doped with relatively small amounts of PSQ3 exhibited greatly improved holographic recording characteristics, including superior diffraction efficiency and dynamic range (M#). Among the samples co-doped with PQ and PSQ3, the maximum diffraction efficiency reached 54.8% (cf. 9.0% for PMMA/PQ) without further downgrade and the value of M# reached 1.05 (cf. 0.46 for PMMA/PQ). Therefore, the holographic data storage characteristics of the photopolymer PMMA/PQ were improved through co-doping with PSQ3.
Effect of doping metal ion on holographic storage characteristics of PQ/poly(hydroxyethyl methacrylate-co-methyl methacrylate) hybrids
(2007-01-01)
Cheng, Wei-Sheng
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Whang, Wha-Tzong
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Chang, Yu-Chia
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Chen, Po-Lin
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Hsiao, Yi-Nan
Holographic Storage Characteristics of PQ/poly(methyl methacrylate) have been significantly improved by doping metallic ion Yb+3 and Er+3. The hybrid materials display significant enhancement in the holographic 13 +3 characteristics. The diffraction efficiency promote to 59% with Yb+3, to 47% with Er from the undoped sample is 40%. The increment is up to 47% in Yb+3 sample; the dynamic range enhance to 2.12 and 1.58 on Yb+3 and Er+3 containing sample individually in comparison to 1.16 for the undoped copolymer. The increment of dynamic range is up to 82% for Yb+3 containing sample. The related mechanism of these changes is preliminary discussed with the analysis of UV-vis, FT-IR and Photoluminescence spectroscopy.
Effect of doping metal ion on holographic storage characteristics of PQ/poly(hydroxyethyl methacrylate-co-methyl methacrylate) hybrids - art. no. 66201K
(2007)
Cheng, Wei-Sheng
;
Whang, Wha-Tzong
;
Chang, Yu-Chia
;
Chen, Po-Lin
;
Hsiao, Yi-Nan
Holographic Storage Characteristics of PQ/poly(methyl methacrylate) have been significantly improved by doping metallic ion Yb+3 and Er+3. The hybrid materials display significant enhancement in the holographic 13 +3 characteristics. The diffraction efficiency promote to 59% with Yb+3, to 47% with Er from the undoped sample is 40%. The increment is up to 47% in Yb+3 sample; the dynamic range enhance to 2.12 and 1.58 on Yb+3 and Er+3 containing sample individually in comparison to 1.16 for the undoped copolymer. The increment of dynamic range is up to 82% for Yb+3 containing sample. The related mechanism of these changes is preliminary discussed with the analysis of UV-vis, FT-IR and Photoluminescence spectroscopy.
Embedded biomimetic nanostructures for enhanced optical absorption in thin-film solar cells
(2011-07-04)
Tsai, Min-An
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Han, Hao-Wei
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Tsai, Yu-Lin
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Tseng, Ping-Chen
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Yu, Peichen
Light-management is critical to thin film solar cells due to their usually limited optical absorption in the active layer. Conventional approaches involve employing separate techniques for anti-reflection and light trapping. Here, we demonstrate an embedded biomimetic nanostructure (EBN) that achieves both effects for hydrogenated amorphous silicon (a-Si: H) solar cells. The fabrication of EBNs is accomplished by patterning an index-matching silicon-nitride layer deposited on a glass substrate using polystyrene nanospheres lithography, followed by reactive ion etching. The profile of EBN is then reproduced layer by layer during the deposition of a-Si: H cells. We show that a solar cell with an optimized EBN exhibits a broadband enhanced external quantum efficiency due to both antireflection and light-trapping, with respect to an industrial standard cell using an Asahi U glass substrate which is mostly optimized for light trapping. Overall, the cell with an optimized EBN achieves a large short-circuit current density of 17.74 mA/cm(2), corresponding to a 37.63% enhancement over a flat control cell. The power conversion efficiency is also increased from 5.36% to 8.32%. Moreover, the light management enabled by the EBN remains efficient over a wide range of incident angles up to 60 degrees, which is particularly desirable for real environments with diffused sun light. The novel patterning method is not restricted to a-Si:H solar cells, but is also widely applicable to other thin film materials. (C) 2011 Optical Society of America
Eosin Y/triethanolamine dispersed poly(hydroxyethyl methacrylate-co-methyl methacrylate) photopolymer
(2006)
Lin, Shiuan-Huei
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Hsu, Ken Yuh
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電子物理學系
;
Department of Electrophysics
We develop a new photopolymer, in which a photoinitiator, eosin Y, and a radical generator, triethanolamine, are dispersed in a poly hydroxyethyl methacrylate and methyl methacrylate copolymer matrix. The fabrication and characterization of material for volume holographic recording are presented.
Fabrication and characterization of poly(methyl methacrylate) photopolymer doped with 9,10-phenanthrenequinone (PQ) based derivatives for volume holographic data storage
(2008-02-15)
Lin, Shiuan-Huei
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Chen, Po-Lin
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Hsiao, Yi-Nan
;
Whang, Wha-Tzong
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材料科學與工程學系
We present our studies on the photopolymer of poly(methyl methacrylate) (PMMA) doped with 9,10-phenanthrenequinone based derivatives for volume holographic storage. By introducing different functional groups on the side-chain of 9,10-phenanthrenequinone molecule, the holographic characteristics of the material can be modified. The photoreaction involved with the holographic recording in the samples was investigated by measuring UV-Vis absorption spectrum and mass spectrum. The experimental results show that the similar behaviors were exhibited in these photopolymers. It is found that phase hologram recording in our PQ derivatives doped PMMA photopolymer involves a structure change of the quinone based molecule, which induces a strong change of the refractive index. Experimental characterizations on holographic data storage, including material sensitivity, dynamic range (M#) and bit-error-rate have been performed. We found that, by selecting appropriate functional groups, an improvement in sensitivity and M# for holographic data storage can be achieved. (c) 2007 Elsevier B.V. All rights reserved.
High Extraction Efficiency of GaN-Based Vertical-Injection Light-Emitting Diodes Using Distinctive Indium-Tin-Oxide Nanorod by Glancing-Angle Deposition
(2011-05-01)
Tsai, Min-An
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Wang, Hsun-Wen
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Yu, Peichen
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Kuo, Hao-Chung
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Lin, Shiuan-Huei
The enhanced light extraction and reduced forward voltage of a GaN-based vertical injection light emitting diode (VI-LED) with an indium-tin-oxide (ITO) nanorod array were demonstrated. The ITO nanorod array was fabricated by the glancing-angle deposition method. The employment of ITO nanostructures amplified not only the broadband transmission but also the current spreading. The optical output power of GaN-based VI-LEDs with ITO nanorods was enhanced by 50% compared with a conventional VI-LED at an injection current of 350 mA. The extraction efficiency was dramatically raised from 62 to 93% by the surface ITO nanorods. We also optimized the extraction efficiency of the GaN-based VI-LED with an ITO nanorod array by tuning the thickness of the n-GaN top layer via three-dimensional finite difference time domain (3D-FDTD) simulation. (C) 2011 The Japan Society of Applied Physics
Holographic information recording and reproducing apparatus for the same
(2009-05-14)
Hsieh, Mei-Li
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Lin, Shiuan-Huei
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Wang, Jui-Hsin
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Hsu, Ken-Yuh
;
Chiang, Don-Yau
In a holographic information recording and reproducing apparatus, an optical fiber guides a reference beam toward a recording medium for holographic recording, and a precision rotator is turned, so that the reference beam is incident on the recording medium at different angles and interferes with a data-carrying signal beam to complete the recording of holographic information on the recording medium. To reproduce the holographic information, the optical fiber guides a reading beam, and the reading beam is incident on the recording medium at an angle the same as the reference beam for the recording to reproduce the holographic information stored on the recording medium. With the optical fiber and the precision rotator, a simplified light path system and a wide range of incident angles for the reference and reading beams may be achieved, and the transmissive, reflective, and 90-degree holographic storage techniques may be integrated in one single apparatus.
Holographic recording characteristics and physical mechanism of zinc methacrylate/nitroaniline-co-doped poly(methyl methacrylate)/9,10-phenanthrenequinone photopolymers
(2013-06-01)
Ko, Cheng-Jung
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Chen, Po-Lin
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Hsiao, Yi-Nan
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Lin, Shiuan-Huei
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Whang, Wha-Tzong
In this study we developed an approach to improve the characteristics of photopolymers for holographic data storage. Through codoping different compounds, N,N-dimethyl-4-nitroaniline (DMNA) and zinc methylacrylate (Zn(MA)2), into 9,10-phenanthrenequinone (PQ) doped poly(methyl methacrylate) (PMMA), the diffraction efficiency and the value of dynamic range (M#) have been progressed. We enhanced the diffraction efficiency (from 36.1 to 86.2%) and the dynamic range (M#, from 2.9 to 10.7) of PQ-doped PMMA through codoping with DMNA and Zn(MA)2. Using mass spectrometry and X-ray photoelectron spectroscopy, we investigated the mechanism behind the improvements in optical storage induced by the presence of Zn(MA)2 and DMNA in PMMA/PQ. POLYM. ENG. SCI., 2013. (c) 2012 Society of Plastics Engineers
Low-shrinkage PMMA photopolymer for volume holographic applications
(2007)
Lin, Shiuan-Huei
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Hsu, Ken Y.
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電子物理學系
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Department of Electrophysics
We present the design and fabrication of extra-low shrinkage photopolymer materials for volume holographic recording. Material characterizations show that the material is promising for holographic data storage of sub-tera bytes per disk. It is also suitable for applications of multichannel image processing. Experimental demonstrations on holographic data storage and image processing will be presented.
Method of compensating for pixel migration in volume holographic optical disc (VHOD)
(2012-09-10)
Yu, Yeh-Wei
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Cheng, Chih-Yuan
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Teng, Tun-Chien
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Chen, Cheng-Hsien
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Lin, Shiuan-Huei
Volume holographic optical disc (VHOD) technology is simpler than the angular multiplexing holographic system. However, disc rotation usually causes pixel migration, thus reducing signal quality. This study proposes a special geometrical arrangement to counteract pixel migration. Using paraxial approximation analysis, an optimal geometrical distance ratio, K, is calculated to compensate for pixel migration and improve image quality during disc rotation. The results of approximation analysis are confirmed by both simulation and experimental results. (C) 2012 Optical Society of America
Modeling the Diffraction Efficiency o f Reflective-Type PQ-PMMA VBG Using Simplified Rate Equations
(2018-12-01)
Shih, Bao-Jen
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Chen, Cuan-Wen
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Hsieh, Yu-Hua
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Chung, Te-Yuan
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Lin, Shiuan-Huei
A simulation based on the rate equations was performed to analyze the concentration distribution of molecules in phenanthrenequinone (PQ) doped polymethyl methacrylate (PMMA) polymers (PQ-PMMAs) exposed using a two-beam interference configuration. The concentration distributions were used to predict the diffraction efficiency of PQ-PMMA-based volume Bragg gratings (VBGs) by using the transfer matrix method. The simulation results suggest that an intermittent exposure method can promote the diffusion of PQ molecules and increase the final diffraction efficiency. A series of experiments validated our hypothesis that the diffraction efficiency of reflective-type PQ-PMMA VBG can be predicted.
Near-infrared sensitive organic-inorganic photorefractive device
(2016-10)
Marinova, Vera
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Liu, Ren-Chung
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Lin, Shiuan-Huei
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Chen, Ming-Syuan
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Lin, Yi-Hsin
Organic-inorganic hybrid structure, assembled by Rh-doped Bi12TiO20 crystal and liquid crystal (LC) layer, operating at near-infrared range is proposed and demonstrated. Due to the photorefractive properties of inorganic substrate, light illumination caused a space charge field which acts as a driving force for LC molecules re-alignment and subsequent refractive index modulation. All optically controlled phase retardation ability has been demonstrated supporting possibilities for further infrared applications.
Near-infrared sensitive organic-inorganic photorefractive device
(2016-10-01)
Marinova, Vera
;
Liu, Ren-Chung
;
Lin, Shiuan-Huei
;
Chen, Ming-Syuan
;
Lin, Yi-Hsin
Organic-inorganic hybrid structure, assembled by Rh-doped Bi12TiO20 crystal and liquid crystal (LC) layer, operating at near-infrared range is proposed and demonstrated. Due to the photorefractive properties of inorganic substrate, light illumination caused a space charge field which acts as a driving force for LC molecules re-alignment and subsequent refractive index modulation. All optically controlled phase retardation ability has been demonstrated supporting possibilities for further infrared applications.
Nitroanilines enhancing the holographic data storage characteristics of the 9,10-phenanthrenequinone-doped poly(methyl methacrylate) photopolymer
(2013-01-05)
Ko, Cheng-Jung
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Hsiao, Yi-Nan
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Lin, Shiuan-Huei
;
Chen, Po-Lin
;
Whang, Wha-Tzong
This article describes an approach toward improving the characteristics of a photopolymer for holographic data storage application. The maximum diffraction efficiency (?max) and dynamic range (M#) of 9,10-phenanthrenequinone (PQ)-doped poly(methyl methacrylate; PMMA) both improved significantly after co-doping with one of three nitroanilinesN,N-dimethyl-4-nitroaniline (DMNA), N-methyl-4-nitroaniline (MNA), and 4-nitroaniline (pNA). In particular, the value of ?max increased from 38% for the PMMA/PQ system to 72% for the PMMA/PQ/DMNA system (a 1.89-fold improvement) and the value of M# increased accordingly from 2.7 to 7.3 (a 2.70-fold improvement). Thus, the holographic data storage characteristics of PMMA/PQ photopolymers can be improved through co-doping with nitroaniline compounds. We also investigated the mechanism of the nitroaniline-induced improvement in optical storage performance using proton nuclear magnetic resonance and X-ray photoelectron spectroscopy. (C) 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2012
Numerical Study of In0.15Ga0.85N/GaN MQW Solar Cells with varying well band structure
(2013)
Wang, Hsun-Wen
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Hsieh, Chi-Chang
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Lai, Fang-I
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Lin, Shiuan-Huei
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Kuo, Hao-Chung
The photovoltaic properties of 14 pairs In0.15Ga0.85N/GaN multiple quantum well solar cells with varying indium composition of QW are investigated numerically. The simulation results show that smooth well structure of energy band can be reduce carrier confinement and the recombination to enhance photo-current generation. This helpful design is easy to improve carrier transport to collection. And the optimal In0.15Ga0.85N/GaN MQW solar cell had V-oc of 2.37V, J(sc) of 0.73, and the efficiency of 0.79%, which the efficiencies is enhanced 69.2 % to reference cell.
Optimization of holographic data storage system based on Seidel aberrations reduction
(2015-01-01)
Liu, Ren-Chung
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Lin, Shiuan-Huei
;
Hsu, Ken-Yuh
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電子物理學系
;
光電工程學系
In this research, we investigate the influence of Seidel aberrations on the point spread function and the probability density function of holographic data storage systems, and thus the storage capacity and bit error rate of storage system can be obtained. The aberrations tolerances of storage systems with different numerical aperture are obtained. Optimization on BER and SC of holographic data storage systems by reducing Seidel aberrations will be demonstrated numerically.