國立虎尾科技大學 |

Control of light propagation by optical indexmodulation for energy applications.

紀錄類型:	書目-語言資料,印刷品 : Monograph/item
正題名/作者:	Control of light propagation by optical indexmodulation for energy applications./
作者:	Kuo, Mei-Ling.
面頁冊數:	101 p.
附註:	Source: Dissertation Abstracts International, Volume: 73-05, Section: B, page: .
Contained By:	Dissertation Abstracts International73-05B.
標題:	Alternative Energy. -
電子資源:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3496398
ISBN:	9781267157485

Control of light propagation by optical indexmodulation for energy applications.
Kuo, Mei-Ling.

Control of light propagation by optical indexmodulation for energy applications. - 101 p.

Source: Dissertation Abstracts International, Volume: 73-05, Section: B, page: .

Thesis (Ph.D.)--Rensselaer Polytechnic Institute, 2011.

To maximize the efficiency of collection or extraction in terms of controllability of photons is one of the solutions to overcome the hurdle of the global energy crisis. By engineering the optical index of materials to create complex network structure, the light propagation is able to be modified as well as their optical properties, such as reflection, transmission, diffraction, absorption and emission. Moreover, advances in nanotechnology, present an unprecedented opportunity to explore strong photon-structure interaction and to manipulate the basic optical modes. In this study, we modulate the optical index of material and nanostructure to control the flow of the light and the optical modes guided or trapped in terms of a need for energy-efficient photonics. Two cases of photon controlling are investigated. One is the graded-index multilayer antireflection coating for maximizing collection efficiency. The other is the randomness 2-demensional (2D) array of light emitting diode for enhancing extraction efficiency.

ISBN: 9781267157485Subjects--Topical Terms:

845381
Alternative Energy.

Control of light propagation by optical indexmodulation for energy applications.
LDR:05211nam 2200325 4500 001 712978
005 20121003100326.5
008 121101s2011 ||||||||||||||||| ||eng d
020 $a 9781267157485
035 $a (UMI)AAI3496398
035 $a AAI3496398
040 $a UMI $c UMI
100 1 $a Kuo, Mei-Ling. $3 845531
245 1 0 $a Control of light propagation by optical indexmodulation for energy applications.
300 $a 101 p.
500 $a Source: Dissertation Abstracts International, Volume: 73-05, Section: B, page: .
500 $a Adviser: Shawn-Yu Lin.
502 $a Thesis (Ph.D.)--Rensselaer Polytechnic Institute, 2011.
520 $a To maximize the efficiency of collection or extraction in terms of controllability of photons is one of the solutions to overcome the hurdle of the global energy crisis. By engineering the optical index of materials to create complex network structure, the light propagation is able to be modified as well as their optical properties, such as reflection, transmission, diffraction, absorption and emission. Moreover, advances in nanotechnology, present an unprecedented opportunity to explore strong photon-structure interaction and to manipulate the basic optical modes. In this study, we modulate the optical index of material and nanostructure to control the flow of the light and the optical modes guided or trapped in terms of a need for energy-efficient photonics. Two cases of photon controlling are investigated. One is the graded-index multilayer antireflection coating for maximizing collection efficiency. The other is the randomness 2-demensional (2D) array of light emitting diode for enhancing extraction efficiency.
520 $a An antireflection (AR) coating is a type of coating applied to the surface of a material to reduce light reflection and to increase light transmission. The coating can improve solar collection efficiency and, therefore, the overall solar-to-electricity efficiency. A theoretical calculation predicts an extremely low reflectance using the concept of a multi-layer graded index profile. The graded-index approach is shown to achieve this goal by offering a mechanism for minimizing Fresnel reflection that is fundamentally different from either the traditional lambda/4 AR-coating or the modified surface structures. Multi-layer nanostructure AR-coating was engineered to dramatically reduce optical reflection over all wavelengths of sun light and incident anglestheta. Our experimental result illustrates that solar-to-electrical conversion efficiency increases by 22.2% when going from a conventional single-layer lambda/4 to a seven layer graded index AR-coating.
520 $a Contrary to the collection efficiency, a conventional planar light-emitting diode (LED) is facing the challenge of low extraction efficiency due to total internal reflection which traps the generated light inside the high index material. The sub-wavelength size of a nanostructure LED can reduce light trapping inside an LED and lead to an enhanced extraction-efficiency. Furthermore, the non-planar surface morphology of a nano-LED array may scatter the emission light and also change the light emission direction and its polarization state. In this study, optical properties of random array nanorod LED were investigated. The result shows that this randomness not only enhances light-extraction, but also modifies light polarization. 3-fold extraction enhancement is achieved. It suggests the enhancement of light output-power in the nano-LED is due to the increasing of the light extraction efficiency by the nano-size effect and random scattering of light.
520 $a Moreover, in order to realize the mechanism of individual nano rod playing the role of extraction enhancement, there is a need to study the optical mode guided or transmitted within single nanorod LED. We fabricated nanorod LEDs in cylindrical shape with diameter d=8mum to 50nm and characterized the optical properties of that systematically by micro-photoluminescence measurement. In this study, we demonstrate that it is possible to completely eliminate TE guided modes inside a nano-rod LED and accomplish an extraction efficiency of 79%from the top surface without the use of a back reflector or a thin film. The keys to this success are to place the quantum wells inside the nano-LED and to reduce the rod-diameter to a sub-lambda confinement regime ( d/lambda ≤ 0.20 ).
520 $a In addition, we incorporated nanostructure on thin-film flip chip LED which structure is based on flip-chip LED with substrate removed. Surface roughness on thin-film flip chip LED by simple dry etching process was produced. Both angular-photoluminescence and absorption efficiency were performed to examine photon extraction. 5.5 times of extraction enhancement is achieved. Extraction enhancement is dominated by density of cone-like shape. The optimization is observed when etching process duration is 300 second.
590 $a School code: 0185.
650 4 $a Alternative Energy. $3 845381
650 4 $a Physics, Optics. $3 845404
690 $a 0363
690 $a 0752
710 2 $a Rensselaer Polytechnic Institute. $3 845532
773 0 $t Dissertation Abstracts International $g 73-05B.
790 1 0 $a Lin, Shawn-Yu, $e advisor
790 $a 0185
791 $a Ph.D.
792 $a 2011
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3496398