Dissertations / Theses: 'Light reflection'

1

Taguchi, Kazue. "LLUM: Light and Reflection." VCU Scholars Compass, 2007. http://hdl.handle.net/10156/1527.

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Anderson, Brian Benjamin. "Grating light reflection spectroscopy /." Thesis, Connect to this title online; UW restricted, 1996. http://hdl.handle.net/1773/8600.

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Schnieders, Dirk. "Light source estimation from spherical reflections." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B45892970.

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4

Patel, Dhara Yogendra. "Reflection." Thesis, Virginia Tech, 2011. http://hdl.handle.net/10919/32832.

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â Reflectionâ is an experiment with what I call â symbolic architectureâ i.e. design where the features of the building have a profound meaning or a strong recall to some familiar aspect in our lives. It is a meditation center designed to rejuvenate visitors by providing an ideal environment to practice and teach meditation. The design is inspired by concepts of Hindu philosophy and each element of the building, the light, the materials, the water and the structure is likened to an element of the spiritual being that helps a meditator achieve a connection between the body and the soul.
Master of Architecture

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5

Ouellette, Guy René. "Nonimaging light concentration using total internal reflection films." Thesis, University of British Columbia, 1991. http://hdl.handle.net/2429/30246.

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Here is presented a method of fabricating nonimaging light concentrators from total internal reflection film (TIRF). Prototypes have been made and tested, and found to operate in agreement with predictions of ray-tracing codes. The performance is comparable with that of concentrators made from specular reflecting materials.
Science, Faculty of
Physics and Astronomy, Department of
Graduate

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Azadeh, Mohammad. "Reflection and Refraction of Light from Nonlinear Boundaries." PDXScholar, 1994. https://pdxscholar.library.pdx.edu/open_access_etds/4715.

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This thesis deals with the topic of reflection and refraction of light from the boundary of nonlinear materials in general, and saturating amplifiers in particular. We first study some of the basic properties of the light waves in nonlinear materials. We then develop a general formalism to model the reflection and refraction of light with an arbitrary angle of incidence from the boundary of a nonlinear medium. This general formalism is then applied to the case of reflection and refraction from the boundary of linear dielectrics. It will be shown that in this limit, it reduces to the well known Fresnel and Snell's formulas. We also study the interface of a saturating amplifier. The wave equation we use for this purpose is approximate, in the sense that it assumes the amplitude of the wave does not vary significantly in a distance of a wave length. The limits and implications of this approximation are also investigated. We derive expressions for electric field and intensity reflection and transmission coefficients for such materials. In doing so, we make sure that the above mentioned approximation is not violated. These results are compared with the case of reflection and refraction from the interface of a linear dielectric.

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Pietsch, Christopher Alexander. "Reflections of Color and Light." Thesis, Virginia Tech, 2014. http://hdl.handle.net/10919/50419.

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An integral part of human vision is the perception of color through the reflection of light. At any moment the human eye is receiving a complex polychromatic reflection of its environment, and the human mind is perceiving many hundreds or thousands of colors. In architecture, light is often a primary consideration in a design, but color is rarely discussed. It makes its presence known, however, as the light entering into a building will carry with it the reflections of the environment. The elements of architecture appear quite different at varying times of the day; at varying times of the year. Even at the same time of day two walls painted the same color will appear as two different colors if placed in different light conditions. This thesis attempts to capture this phenomenon and elaborate on the possibilities of working with light through reflection. It is not meant to give a specific answer, but rather to show the results of a search to find a way of working with light through color.
Master of Architecture

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Zeng, Zheng. "Reflection and absorption of light in butterfly wing scales /." View abstract or full-text, 2008. http://library.ust.hk/cgi/db/thesis.pl?PHYS%202008%20ZENG.

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Nordqvist, Amanda. "Colour and light." Thesis, Högskolan i Borås, Akademin för textil, teknik och ekonomi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-10378.

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This work explores how colour and light can be used as the prime design materials. They are investigated in unison in relation to spatiality. Colour is a way for us to understand and identify what we see, it is primary for how we interpret our surroundings. The aim is to explore colour, light and reflections, by the means of printing and dyeing of translucent materials, as an attempt to challenge the visual perception of the spectator and the experience of how spatiality is perceived. The project investigates how the boundaries of a textile can be questioned, for example where does a pattern begin and end? Does it only belong to the textile or can it transcend to it’s surroundings? The investigational process is experimental and explores combinations of colour and light in translucent materials, coloured through the techniques of heat transfer printing and dyeing. Swatches made are analysed in relation to each other and to light, with a focus on their visual performance. The final design examples discusses the idea of how textile, light and colour can be used to create, define and illuminate spatiality.

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Smith, Sean A. "Development of grating light reflection spectroscopy for chemical sensing applications /." Thesis, Connect to this title online; UW restricted, 2000. http://hdl.handle.net/1773/11592.

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Weis, R. Stephen. "Electromagnetic transmission and reflection characteristics of anisotropic multilayered structures." Diss., Georgia Institute of Technology, 1987. http://hdl.handle.net/1853/13546.

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Romer-Jordan, Zachary L. "The Threshold of Experience: A Journey Toward Inward Reflection." University of Cincinnati / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1275667134.

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Porritt, Dawn, and n/a. "The magnificent play of light: seeing the difference." University of Canberra. Design and Architecture, 2007. http://erl.canberra.edu.au./public/adt-AUC20081023.115855.

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Light as a concept is filled with a multitude of interpretations, ideas and possibilities and no matter how technologically progressive we think we are, nature consistently controls our human way of life. We are surrounded by nature and often gain inspiration by the simple things around us. My interest in the phenomena of light and refraction was sparked years ago by Claude Monet?s painting Bathers at La Grenouillere, 1869. It showed simplicity of form and shape, yet emitted a luminosity and radiance of light reflecting off water. This thesis examines the subject of light as an optical phenomenon. My specific aim was to create distorted, ambiguous and conflicting images in my photographs by using the "optical phenomena" of light such as, refraction, diffraction and reflection as a basis for abstracting reality. I wanted to capture the changes that occur when light changes direction due to refractive qualities within a material such as glass, water or plastic, or due to the reflective qualities of a surface. The camera was exploited for its capacity to capture realism, but also to capture and abstract natural phenomenon. The images were enlarged to magnify details and the reality of the physical world was heightened as objects became ambiguous. Design compositional techniques were used to decontextualise objects. I approached this study with the idea that observation and awareness has importance to image making within my design and teaching practice. This thesis presents my project explorations showing the play of light on and through surfaces under different conditions. I have documented this by producing a series of photographic images and a glossary as an aid in the practice of design education.

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Stiles, Mary. "The art of light : a reflection on a piece for orchestra." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq48230.pdf.

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Hamad, Mazen Lee. "Exploring and developing the instrumental aspects of grating light reflection spectroscopy /." Thesis, Connect to this title online; UW restricted, 2003. http://hdl.handle.net/1773/8610.

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Iafelice, Vincent John. "THE POLARIZED LIGHT SCATTERING MATRIX ELEMENTS FOR SELECT PERFECT AND PERTURBED OPTICAL SURFACES (MUELLER, MIRRORS, O)." Thesis, The University of Arizona, 1985. http://hdl.handle.net/10150/275450.

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Salmons, John Andrew. "Adopting an Orphaned Collection." Thesis, Virginia Tech, 2016. http://hdl.handle.net/10919/64789.

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"Architecture itself is linked not only to other arts but also to the broader context of life; it is only on that scale that we may understand its specific contribution to the formation of the communicative space of culture."* - Dailbor Vesely 2004 Architects have explored Art Galleries as a medium throughout the ages. In 2014, the Corcoran was sold, dismantled and divided between the National Gallery of Art and George Washington University signaling the end of an era of art display in the Nation's Capital. This transformation of a major DC art collection was the impetus for this thesis: to mark the end of an era and to create a new home for the Corcoran Collection. To house this orphaned collection, I have studied similar elements that earlier architects have studied such as light, shadow, and reflection, taking into account the dawn of the next generation of art galleries. The role of this museum is to educate and facilitate information about the collection and the art. Contemporary art galleries that have been built recently included additional areas of services that were originally not part of the Corcoran Museum's building program, such as the role of conservation of historical objects including paintings and works on paper. Another area of my research was the relationship between the viewer and the building. The Corcoran has an extensive collection of American art and art directly from D.C. and it is important to allow direct access for the community and accommodate enough wall space to give context to the art. With the setting of the contemporary art gallery framed, we return back to the research to really question how each of those elements were thought about moving forward. We need light to see, but what had been seen and depicted on great Master's canvases should be protected from light. Should natural light be brought into the gallery spaces even though it damages works on canvas and paper? Can gallery spaces change over time to mirror the objects that they hold? Can the building reflect the area around the gallery but also act as a space of meditation and self-reflection? To adopt means to take another's child, but it can also mean to embrace an idea. In this case we are adopting the collection of William Corcoran and combining it with newer elements found in modern museums. On further evaluation of the gallery it has strong ties to historic D.C. because of its collection and its community outreach however its weakness was due in part of turning its back on the same community that made it strong. I propose moving the collection into the heart of Washington D.C. and combining it with newer ideas of light and gallery services. This process will allow the Corcoran to continue its evolution as a great American collection. *Dailbor Vesely, "Architecture in the Age of Divided Representation." (Cambridge: The MIT Press, 2004), 88-89.
Master of Architecture

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18

Török, P. "Development, theory and application of the reflection confocal scanning infra-red microscope." Thesis, University of Oxford, 1994. http://ora.ox.ac.uk/objects/uuid:cf94a26c-aedc-46cc-b179-542627f59ccd.

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Czochralski (Cz) silicon wafers are used almost exclusively for the fabrication of VLSI devices. Such silicon contains excess oxygen which precipitates as oxide particles either when the initial ingot is grown or subsequently during the wafer device fabrication. Such oxide particles can produce reduced device performance or failure if they occur within the active device regions. However, they can be used to improve the device performance by a process known as internal oxide gettering. The wafers are given a series of preanneal treatments to produce controlled precipitation in which a surface zone of the wafer to a depth of typically in the range of 10 to 50 μm is denuded of oxide particles, while the remainder of the wafer contains large numbers of well formed particles. The devices are fabricated in the surface denuded zone and harmful contaminating metal impurities are attracted during the heat treatment stages away from the device regions to precipitate at the underlying oxide particles or their associated dislocations. In this way device yields can be significantly increased. Because of the importance of these oxide particles and the oxygen precipitation process for VLSI fabrication, considerable efforts have been made to develop methods to assess the numbers and distributions of such particles within the wafers. The number density range of most interest is 10⁷ to 10¹⁰ cm^-3, and the particle size range is typically 30 to 300 nm. The method that has mostly been used is surface etching followed by optical microscopy to obtain etch pit densities. Transmission electron microscopy is a research method used for obtaining detailed information concerning a small number of individual particles. However, because these methods are destructive, much attention has been given during the last few years to the development of infra-red microscopy methods to directly image the particles within the silicon wafers. Although the particles are smaller than the resolution of these methods, individual particles can nevertheless be imaged. This is because the particles are mostly further apart than the resolution limit, and the sensitivity can be sufficient high that adequate contrast occurs. The contrast arises from scattering or absorption of the light by the particle. Infra-red imaging methods developed include infra-red microscopy (IRM), laser scattering tomography (LST), optical precipitate profiler (OPP) and scanning infra-red microscopy (SIRM), all described more fully in Chapter 2. The SIRM has been developed and used to investigate a variety of semiconductor specimens in the Materials Department, Oxford University, during the last ten years. The SIRM has a good performance and flexibility making it especially suitable as a research instrument. Although all of these infra-red imaging methods have been successful to different degrees in assessing oxide particles in Cz silicon wafers, their performance has at least initially been assessed by comparing the number densities and distributions thus obtained with the corresponding results produced by etch pit studies. Furthermore, no serious attempt has yet been made to develop a rigorous theory of the imaging process and to compare the predictions with the experimental images. One of the main objectives of the present work is to do this or at least to make a significant start to such a project based on the SIRM. The outline of an ideal project which aims at a full understanding of the imaging process and the contrast mechanisms is as follows. The performance of the present Oxford SIRM should be improved and the number of imaging modes increased. The improved performance, i.e. better lateral and depth resolutions and higher sensitivity, would enable smaller particles and higher number densities to be imaged, and hence better quantitative data obtained. The larger number of imaging modes would enable the optimum method to be used to image different types of particle. A rigorous theory should be developed that can describe the imaging process and the contrast mechanisms. First, the illumination system should be studied, and in particular the structure of the focussed probe within the specimen and how the structure changes on focussing deeper into the specimen. Second, the interaction of the light with the specimen should be investigated and especially how light is scattered by individual oxide particles in silicon for the case of the particle size being smaller than the light wavelength. Third, the detection system should be considered. For example, for the reflection confocal SIRM, how the light back scattered by the particles is collected by the probe forming lens and imaged at a pin-hole aperture placed in the front of the detector. Well designed experiments are required to determine the imaging properties of the different modes and comparisons should be made between the experimental and theoretical data. The successful conclusion of such a project would enable SIRM images of the particles to be more fully interpreted and hence more detailed information obtained concerning the particles. Furthermore, the images expected from different types of particle could be more closely predicted, e.g. whether they are detectable or not, and hence materials projects could be better planned at the outset. In this thesis we describe the methods that are presently being used to assess oxide particles in bulk silicon (Chapter 2). We review the literature on scanning optical microscopy covering both visible and infra-red light, present some considerations regarding the design of a high performance and versatile SIRM, and describe the various microscope modes that have been or could be used to image particles in semiconductors with infra-red light (Chapter 3). We give a detailed rigorous theoretical analysis of the energy distributions in the probe for the case when the light is focussed by a high numerical aperture lens from air into silicon (Chapters 4, 5). Numerically computed distributions are obtained to illustrate how the probe changes under different conditions, e.g. different focussing depths (Chapter 6). The relationship between the penetration depth of the probe and the spherical aberration coefficient arising from the silicon specimen is determined (Chapter 7). The classical theory of light scattering is applied to individual spherical silicon dioxide particles embedded in silicon. Numerical results are presented and a contrast mechanism is proposed to describe how the scattered intensity depends on particle size (Chapter 8). A formal solution relevant to the reflection confocal SIRM is given to treat the backward propagation of light using a model which takes into account the polarisation state of the incident light, the spherical aberration introduced by the silicon wafer, the polarisation state of the scattered light and the size of the pin-hole (Chapter 9). Experimental results are obtained for most of the imaging modes described in Chapter 3, specimens being selected so that the wide range of the imaging capabilities of the SIRM is shown, and experimental contrast values are compared with theoretical values (Chapter 10). Finally, overall conclusions are drawn and suggestions are made for completing the work started here (Chapter 11).

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19

Bilmont, Marsha F. "FURTHER INVESTIGATIONS INTO SURFACE STRUCTURE AND THE BIDIRECTIONAL REFLECTANCE DISTRIBUTION FUNCTION (LIGHT-SCATTER, ROUGHNESS, PROFILOMETRY)." Thesis, The University of Arizona, 1985. http://hdl.handle.net/10150/275398.

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20

Fan, Xiaofei Yao Gang. "Study of human pupillary light reflex and its potential application in autism." Diss., Columbia, Mo. : University of Missouri--Columbia, 2009. http://hdl.handle.net/10355/6973.

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Title from PDF of title page (University of Missouri--Columbia, viewed on Feb 26, 2010). The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Dissertation advisor: Dr. Gang Yao. Vita. Includes bibliographical references.

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Hodgkin, Van Arlen. "Accurate measurement of the phase shift on reflection of light from opaque materials." Diss., The University of Arizona, 1994. http://hdl.handle.net/10150/186909.

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Because the phase shift on reflection is a function of the optical properties, it provides an excellent tool for the study of the microstructure of materials. However, there is a significant amount of confusion and error in its measurement in previous work. Therefore, a new method for accurately measuring the phase shift on reflection from opaque materials that is based upon a mathematical comparison of step height measurements made with stylus and phase shifting interferometric profilometers is presented. The presentation of this new measurement method consists of a comprehensive account of its theoretical and experimental basis and validation. The theoretical portion begins with the development of the initial mathematical models used for calculating the phase shift from stylus and afocal, normal incidence interferometric step height measurements and verifying the results with the Fresnel relations. As a result of the first measurements, both the measurement and verification models are modified to account for the use of focused, unpolarized light by the interferometric profilometer, and the verification model is also modified to include the possible existence of a dielectric overlayer on the surface of the opaque material. The experimental portions consist of the descriptions and results of accurate step height measurements made with a Rank Taylor Hobson Talystep diamond stylus profilometer and a Wyko TOPO-2D interferometric surface profiling system. Also included are comprehensive descriptions of both profilometers and their operation, and accurate assessments of the number and magnitude of sources of experimental error. The opaque materials used to demonstrate and validate this technique consisted of thick films of chromium on glass and gold on fused silica. The phase shifts, which were measured at different locations on each of the samples, are verified with the predictions of published values of the optical and structural properties of the particular material, and the averages of the measured phase shifts agreed extremely well with those predictions. In the gold measurements, which had a precision of 0.7%, a 4% spatial variation in the phase shift on reflection was discovered and strongly supported by a second set of measurements with a refined version of the experimental technique.

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Renkoski, Timothy Eli. "Study of a high frequency electro-optic beam deflector utilizing reflection-based velocity matching /." free to MU campus, to others for purchase, 2004. http://wwwlib.umi.com/cr/mo/fullcit?p1422958.

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23

Mikutavičius, Mantas. "Laiko mašina magistro baigiamojo darbo aiškinamasis raštas." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2014. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2014~D_20140703_160719-37948.

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Laiko mašina Laiko mašina - neišrastas, bet kiekvieną dieną matomas daiktas - veidrodis. Matomas atspindys veikia pasamonę, o besikeičianti šviesa - apmąstymus: kas buvo lieka už nugaros, kas bus stovi prieš mus. Aš svajoju, žvelgiu į dangų, neišsipildžiusios svajonės žvelgiu žemyn. Lygiagrečiai susiduriame su kasdieniniais pasirinki-mais - kairė ar dešinė. O viso to centras esu AŠ.
The Time Machine The Time Machine - invented, but every day visible object - a mirror. Visible reflection does the subconscious mind and changing light - reflection: What has been left behind, who will be standing in front of us. I dream, I look at the sky, I look down unfulfilled dreams. In parallel, we encounter everyday-tion's choice - left or right. And all that I am the center.

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24

Hermansson, Andreas. "Simulation of line fault locator on HVDC Light electrode line." Thesis, University West, Department of Engineering Science, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:hv:diva-2620.

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In this bachelor thesis, cable fault locators are studied for use on the overhead electrode lines in the HVDC (High Voltage Direct Current) Light project Caprivi Link. The cable fault locators studied operates with the principle of travelling waves, where a pulse is sent in the tested conductor. The time difference is measured from the injection moment to the reflection is received. If the propagation speed of the pulse is known the distance to the fault can be calculated. This type of unit is typically referred to as a TDR (Time Domain Reflectometer). The study is performed as a computer simulation where a simplified model of a TDR unit is created and applied to an electrode line model by using PSCAD/EMTDC. Staged faults of open circuit and ground fault types are placed at three distances on the electrode line model, different parameters of the TDR units such as pulse width and pulse amplitude along with its connection to the electrode line are then studied and evaluated. The results of the simulations show that it is possible to detect faults of both open circuit and ground fault types with a suitable TDR unit. Ground faults with high resistance occurring at long distances can be hard to detect due to low reflection amplitudes from the injections. This problem can somewhat be resolved with a function that lets the user compare an old trace of a “healthy” line with the new trace. The study shows that most of the faults can be detected and a distance to the fault can be calculated within an accuracy of ± 250 m. The pulse width of the TDR needs to be at least 10 μs, preferable 20 μs to deliver high enough energy to the fault to create a detectable reflection. The pulse amplitude seams to be of less significance in this simulation, although higher pulse amplitude is likely to be more suitable in a real measurement due to the higher energy delivered to the fault. The Hipotronics TDR 1150 is a unit that fulfil these requirements and should therefore be able to work as a line fault locator on the electrode line.

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Ang, Jason. "Offset Surface Light Fields." Thesis, University of Waterloo, 2003. http://hdl.handle.net/10012/1100.

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For producing realistic images, reflection is an important visual effect. Reflections of the environment are important not only for highly reflective objects, such as mirrors, but also for more common objects such as brushed metals and glossy plastics. Generating these reflections accurately at real-time rates for interactive applications, however, is a difficult problem. Previous works in this area have made assumptions that sacrifice accuracy in order to preserve interactivity. I will present an algorithm that tries to handle reflection accurately in the general case for real-time rendering. The algorithm uses a database of prerendered environment maps to render both the original object itself and an additional bidirectional reflection distribution function (BRDF). The algorithm performs image-based rendering in reflection space in order to achieve accurate results. It also uses graphics processing unit (GPU) features to accelerate rendering.

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Stigborg, Christina. "Light It Up - Designproces af en spisebordslampe." Thesis, Malmö universitet, Fakulteten för kultur och samhälle (KS), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-23543.

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This thesis studies how to design a light to a target group based on different theories and methods. The aim has been to investigate what factors are needed to design a good lamp based on theories developed by Poul Henningsen. The problem definition for this study is as follows: How can you use the ACD methods and design process to design a dining table lamp based on Poul Henningsen's theories about light?In order to answer the problem definition, a choice was made to work with the theoretical field of User Centered Design. The study is based on empirical evidence of light and methods that will investigate and analyze the specific needs of a target group in regard to a dining table lamp. Using a design process consisting of idea generation, conceptualizing and prototyping, a lamp that meets both the needs of the target group and the requirements of Poul Henningsen has been designed. The result of this was the development of a dining table lamp that has several different adjustment options physically and technically and casts theoretically correct shadows.This study shows how little empiric evidence that currently exist about light and its use. Therefore, there is ample opportunity to do more research on this topic. Additionally, this task opens up the possibility of designing new lamps based on clarified guidelines.

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Chanda, Brian Thomas. "Color, Texture and The Space In-Between: An Architectural Intervention of Stained Glass." Thesis, Virginia Tech, 2016. http://hdl.handle.net/10919/71682.

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This thesis studies the use of stained glass as a building material and how it can enhance the visual presence of light, materiality and space in a building interior. Lighting, color, and texture were integral paths of study which culminated in a stained glass installation at the concrete Cube at the Research + Design Facility in Blacksburg, Virginia. The resulting space becomes a room that reveals a dimension of architectural space not rarely studied or thought about when designing, revealing the way light continually shapes and defines a space throughout the seasons and time of day. The goal of the installation is to highlight ordinary conditions of light and space in a new light through color intervention of the interior.
Master of Architecture

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Patterson, Justin J. "Towards a robust primacy a contemporary reflection on church order, disorder, and the canonical tradition in light of the Roman papacy /." Theological Research Exchange Network (TREN) Access this title online, 2005. http://www.tren.com.

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Chavoor, Greg. "Light Extraction Enhancement of GaN Based LEDs Using Top Gratings, Patterned Sapphire Substrates, and Reflective Surfaces." DigitalCommons@CalPoly, 2012. https://digitalcommons.calpoly.edu/theses/737.

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In the last 15 years, an immense amount of research has gone into developing high efficiency Gallium Nitride based light emitting diodes (LED). These devices have become increasingly popular in LED displays and solid state lighting. Due to the large difference in refractive index between GaN and Air, a significant amount of light reflects at the boundary and does not escape the device. This drawback decreases external quantum efficiency (EQE) by minimizing light extraction. Scientists and engineers continue to develop creative solutions to enhance light extraction. Some solutions include surface roughening, patterned sapphire substrates, and reflective layers. This study proposes to increase external quantum efficiency and optimize light extraction efficiency of several LED structures using finite difference time domain analysis (FDTD). The structures under investigation include GaN based LEDs with nanoscale top gratings, patterned sapphire substrates in combination with SiO2 nanorod arrays, and reflective surfaces below and above the sapphire substrate. First, we optimize GaN based nanoscale top gratings and increase light extraction by 17.8%. Next, we simulate ITO based top gratings and enhance light extraction by 40%. Third, we optimize patterned sapphire substrate period and width and the vertical position of a SiO2 nanorod array. We achieve as high as 51.8% improvement in light extraction. Finally, we increase light extraction by 160% with the use of a silver reflection layer.

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Wasey, Jonathan Arthur Edward. "Spontaneous emission within wavelength-scale microstructures." Thesis, University of Exeter, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.364468.

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Berg, Ingrid. "3Cu." Thesis, Högskolan i Borås, Institutionen Textilhögskolan, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-17095.

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Damiani, Benjamin Mark. "Investigation of Light Induced Degradation in Promising Photovoltaic Grade Si and Development of Porous Silicon Anti-Reflection Coatings for Silicon Solar Cells." Diss., Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/5203.

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Cast multi-crystalline silicon substrates are used in more than 50% of the photovoltaic modules produced today. The random grain orientations of multi-crystalline silicon wafers inhibit the formation of an effective surface texturing using conventional techniques. The other main substrate used is single crystalline Czochralski wafers (~30% of the market share). Czochralski silicon material is known to suffer from the formation of a metastable defect under carrier injection, sometimes referred to as light induced degradation (LID). Light induced degradation in low-cost photovoltaic grade silicon is studied. Trap formation is shown to occur at temperatures above 200oC. Efficiency degradation reduced from 0.75% to 0.24% when the cell thickness was reduced from 378 to 157m. The presence of light induced degradation in ribbon silicon solar cells is documented for the first time in this thesis. Trap generation and annihilation are observed in high lifetime regions of multi-crystalline silicon samples. No degradation was observed over a 24-hour period at 25oC in high efficiency ribbon solar cells (>16%), but at an elevated temperature of ~75oC, appreciable efficiency degradation was observed. Czochralski silicon solar cells showed full degradation within 24 hours at 25o C. Part two of this thesis involves the development of a surface texturing suitable for all crystalline silicon. Only 6 to 10 seconds in a 200:1 HF to HNO3 solution at room temperature allows for the formation of an effective porous silicon anti-reflection coating. This resulted in a porous silicon anti-reflection coated solar cell efficiency of 15.3% on a float zone Si sample with an excellent fill factor (78.7%). The typical process used in the literature involves porous silicon etching as the final step in the solar cell fabrication sequence. The major problem associated with this process sequence is fill factor degradation. This problem was overcome in this research by porous silicon etching prior to cell processing. It is shown that incorporating an acid texture prior to porous silicon etching can improve the surface reflectance for cast multi-crystalline and Czochralski silicon samples. Solar cell efficiencies of 14.8% for Cz Si and 13.6% for cast mc-Si were achieved.

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DRUBSCKY, CAMILA ANDRADE. "TO WHAT DEGREE IS IT CORRECT TO SAY THAT NARCISSISM IS DATED? A REFLECTION UNDER THE LIGHT OF PIERA AULAGNIER´S CONTRIBUTION." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2008. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=11780@1.

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CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO
Esta tese propõe-se a refletir sobre o sofrimento humano na contemporaneidade. O maior empenho foi no sentido de não cometer generalizações apressadas, quase sempre reducionistas. Para tanto, procurou-se estabelecer uma interlocução com psicanalistas que, assim como nós, reconhecem que determinados tratamentos são refratários ao modelo clássico da psicanálise e, por isso, estão dispostos a ampliar o seu repertório teórico-clínico seguindo as pegadas de Freud, sem destituir jamais o seu legado. Privilegiaram-se, a partir da leitura da psicanalista Piera Aulagnier, as noções de violência, pictograma, alienação e paixão. A ideia de narcisismo moral, um dos destinos do conceito de narcisismo desde Freud, segundo o psicanalista André Green, foi também apresentada. Queremos supor que, realizado o percurso descrito, podemos sustentar a convicção de que precisamos continuar escutando o sujeito que sofre e não o sujeito contemporâneo, posto que só o primeiro é passível de tratamento.
This thesis intends to reflect on the human suffering in the nowadays. The main effort was to avoid generalizations, which are frequently very limited. We attempted to establish a dialogue with analysts who acknowledge the fact that certain treatments resist the classical frame of psychoanalytic treatment. These analysts are willing to expand their theoretical and clinical repertoire without abandonning Freud`s legacy. From the work of Piera Aulagnier, we singled out the concepts of violence, pictogram, alienation and passion. The notion of moral narcisism, according to André Green formulations, was also presented. By going through the ideas mentioned above, we would like to state that we must keep listening to the human being who is suffering and not to the contemporary man, since only the former is eligible to undergo a psychoanalytic treatment.

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Levy, Cecilia [Verfasser], and Christian [Akademischer Betreuer] Weinheimer. "Light propagation and reflection off teflon in liquid xenon detectors for the XENON100 and XENON1T dark matter experiments / Cecilia Levy ; Betreuer: Christian Weinheimer." Münster : Universitäts- und Landesbibliothek Münster, 2014. http://d-nb.info/113828226X/34.

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Dietz, Otto. "Linear and non-linear properties of light." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät, 2016. http://dx.doi.org/10.18452/17474.

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Alle optischen Systeme haben den gleichen Zweck: Sie manipulieren Eigenschaften des Lichts, durch Interaktion mit Materie. In dieser Arbeit werden zwei wichtige Teilaspekte aus diesem Kontext untersucht, im linearen und im nicht-linearen Bereich. In Teil I werden die bekannten Bragg-Reflexionen in neuem Licht betrachtet. Bragg Reflexion findet statt, wenn Licht mit einem periodischen Medium interagiert. Die Bragg-Bedingung verknüpft den Gitterabstand in einem Kristall mit der Wellenlänge, die von ihm reflektiert wird. In dieser Arbeit werden die Bragg Reflexionen in gewellten Wellenleitern untersucht. Es wird gezeigt, dass die Bragg-Bedingung nicht ausreicht, um die Streuung in diesen Wellenleitern zu verstehen. Es wird numerisch und analytisch demonstriert, dass unebene Ränder eine neue Reflexionsbedingung schaffen, die über das einfache Bragg-Bild hinausgeht. Dieser Streueffekt, der Square Gradient Bragg-Mechanismus ist aus statistischen Streuansätzen bekannt. Er hängt mit der Krüummung des Randes zusammen und hat einen starken Einfluss auf die Wellenleitung in diesen Systemen. In dieser Arbeit wird die erste allgemeine Theorie für den Square Gradient Bragg Streumechanismus vorgestellt, die es ermöglicht, Voraussagen für einzelne Wellenleiter mit beliebig deformierten Rändern zu treffen. Eine weitere wichtige Eigenschaft des Lichts wird in Teil II dieser Arbeit untersucht: Die Verschränkung zwischen zwei Photonen. Verschränkung ist ein intuitiv nicht verständliches Phänomen, weil es in der uns umgebenden klassischen Welt kein Analogon hat. Insbesondere verletzt es unsere implizite Annahme eines lokalen Realismus, weil voneinander entfernte Teilchen scheinbar instantan miteinander wechselwirken können. In dieser Arbeit wird eine neue und verstimmbare Quelle für verschränkte Photonen entworfen. Die Photonenpaare werden in nicht-linearen Kristallen erzeugt, aber ihre Verschränkung wird rein geometrisch erzwungen. Dieser geometrische Ansatz erlaubt es, die Frequenz der Photonen einzustellen. Hier übertrifft diese neue Quelle ihre Vorgänger, die ausführlich besprochen werden. Die Verschränkung der erzeugten Photonen wird experimentell nachgewiesen.
Any optical experiment, any optical technology is only about one thing: Manipulating the properties of light through interaction with matter. This thesis will address two important issues in this broad context, in the linear and in the non-linear regime. In Part I, the well-known Bragg reflection is revised. Bragg reflection takes place whenever light interacts with a periodic structure. The famous Bragg condition relates the lattice spacing in a crystal to the wavelength which is effectively reflected by that lattice. In this thesis the Bragg reflection in dielectric waveguides is investigated. It is shown that the Bragg condition is not sufficient to describe the scattering situation in waveguides with corrugated boundaries. It is demonstrated, analytically and numerically, that corrugated boundaries cause a new type of reflection condition, which goes beyond the Bragg picture. This scattering mechanism, the Square Gradient Bragg Scattering, is known from statistical scattering approaches. It is connected to the curvature of the boundary and has a strong influence on the wave propagation in these systems. Here the first general theory for Square Gradient Bragg Scattering is presented, which allows for making predictions for single corrugated waveguides with arbitrary boundaries. Another important property of light is investigated in Part II of this thesis: The entanglement of two photons. Entanglement is a counter-intuitive phenomenon, because it has no classical analogy. It especially violates our assumption of local realism, because distant particles seemingly act on each other instantaneously. In this thesis a new tunable and portable source of photon pairs is designed. The photon pairs are created in non-linear crystals, but their entanglement is enforced in a purely geometrical manner. This geometrical approach makes the setup tunable. This is where the new design supersedes its predecessor, which will be discussed in detail. The entanglement of the generated photons is demonstrated experimentally.

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Pospíchal, David. "Systém pro měření lokálních IR spekter." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2021. http://www.nusl.cz/ntk/nusl-442520.

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The diploma thesis deals with the design of a system for measuring infrared spectra from local areas of samples. The theoretical part describes the electromagnetic waves and related phenomena. Furthermore, the semiconductor junction and solar cells are discussed. The following is a basic description of line spectrometers. In the practical part, a suitable arrangement of the whole system, collimator design, and especially the core of the whole work, ie control software and signal processing, are proposed.

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Tripsa, Silvia Casandra. "The Value of Light in Contemporary Memorials : Understanding the needs of contemporary memorials and how they can be accomplished with light. Proposal of a light installation for commemorating the 1989 acticommunist Revolution in Timisoara." Thesis, KTH, Ljusdesign, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-221666.

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The master thesis is a research about the relationship between memorials and light. It first studies the characteristics of cultural memories and tries to find what the advantages of using lighting as a means of commemoration are. The nowadays memorials are very different compared to the traditional monuments and they should include a changing narrative, treating local and universal messages. They should involve the public.A contemporary memorial is ephemeral and continuously changing- the same as light is.A series of contemporary memorials have been selected to understand the tools that makes them successful. Furthermore, it was analyzed how these parameters could be achieved through light. 12 memorials that use light as an eloquent tool have been interpreted according to certain criteria.The second part of the thesis is an applied project related to the events that happened in Timisoara, Romania, in 1989 during the anticommunist Revolution. The process of creating memorials for Timisoara is a key focus of the study. The development is equally important as the end result. It searches for the significant messages and lessons of the event. Testimonials of the participants to the revolution have been studied. Interviews and questionnaires have been developed. Following this, significant places in the city and messages were chosen. The research will conclude with a lighting installations project proposal.

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Foster, Robert. "The polarization of light in coastal and open oceans| Reflection and transmission by the air-sea interface and application for the retrieval of water optical properties." Thesis, The City College of New York, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10254604.

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For decades, traditional remote sensing retrieval methods that rely solely on the spectral intensity of the water-leaving light have provided indicators of aquatic ecosystem health. With the increasing demand for new water quality indicators and improved accuracy of existing ones, the limits of traditional remote sensing approaches are becoming apparent. Use of the additional information intrinsic to the polarization state of light is therefore receiving more attention. One of the major challenges inherent in any above-surface determination of the water-leaving radiance, scalar or vector, is the removal of extraneous light which has not interacted with the water body and is therefore not useful for remote sensing of the water itself. Due in-part to the lack of a proven alternative, existing polarimeter installations have thus far assumed that such light was reflected by a flat sea surface, which can lead to large inaccuracies in the water-leaving polarization signal. This dissertation rigorously determines the full Mueller matrices for both surface-reflected skylight and upwardly transmitted light by a wind-driven ocean surface. A Monte Carlo code models the surface in 3D and performs polarized ray-tracing, while a vector radiative transfer (VRT) simulation generates polarized light distributions from which the initial Stokes vector for each ray is inferred. Matrices are computed for the observable range of surface wind speeds, viewing and solar geometries, and atmospheric aerosol loads. Radiometer field-of-view effects are also assessed. Validation of the results is achieved using comprehensive VRT simulations of the atmosphere-ocean system based on several oceanographic research cruises and specially designed polarimeters developed by the City College of New York: one submerged beneath the surface and one mounted on a research vessel. When available, additional comparisons are made at 9 km altitude with the NASA Research Scanning Polarimeter (RSP). Excellent agreement is achieved between all instrumentation, demonstrating the accuracy of the modeling approach and validating the computed Mueller matrices. Further, the results are used to demonstrate the feasibility for polarimetric retrieval of the total attenuation coefficient for Case II waters, a feat which is not possible using scalar remote sensing methods.

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Wang, Chia-Hao. "Context Awareness." Thesis, Konstfack, Inredningsarkitektur & Möbeldesign, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:konstfack:diva-5870.

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From anti-modernism to the movement of regaining identity, in one way or another, we are all somehow looking for ways to find the harmony in this world. Respecting nature, be aware of the environment and co-exist with it, is worth further investigation. That is why I chose to examine the relationship of context and interior, with the help of natural light.

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Eroglu, Huseyin Cuneyt. "Design Of Reflective &amp." Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/2/12611057/index.pdf.

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In order to improve the efficiency of various optical surfaces, optical coatings are used. Optical coating is a process of depositing a thin layer of a material on an optical component such as mirror or lens to change reflectance or transmittance. There are two main types of coatings namely
reflective and antireflective (AR) Coatings. Reflective and antireflective coatings have long been developed for a variety of applications in all aspects of use
for optical and electro-optical systems in telecommunications, medicine, military products and space applications. In this thesis, the main properties of reflective and antireflective coatings, the thin film deposition techniques, suitable coating materials for space applications, space environment effects on coating materials and coating design examples which are developed using MATLAB for space applications will be discussed.

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Hicks, William L. "Social Discourse in the Savoy Theatre's Productions of The Nautch Girl (1891) and Utopia Limited (1893): Exoticism and Victorian Self-Reflection." Thesis, connect to online resource, 2003. http://www.library.unt.edu/theses/open/20032/hicks%5Fwilliam/index.htm.

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Hebecker, Dustin. "Development of a single photon detector using wavelength-shifting and light-guiding technology." Doctoral thesis, Humboldt-Universität zu Berlin, 2021. http://dx.doi.org/10.18452/23231.

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Das IceCube Neutrino-Observatorium ist ein am geografischen Südpol im Eis installierter Neutrinodetektor. In IceCube werden Neutrinos mit Tscherenkow-Strahlung von Sekundärteilchen aus Neutrino Interaktionen detektiert. Für den Nachfolgedetektor IceCube-Gen2, werden neue und verbesserte Lichtdetektoren gesucht. Die vorliegende Arbeit beschreibt die Entwicklung eines dieser Lichtdetektoren. Dieser basiert auf Wellenlängen schiebenden und Licht leitenden Technologien. Der Detektor mit dem Namen "Wavelength-shifting Optical Module" (WOM) verwendet eine transparente Röhre, mit wellenlängenschiebender Farbe, als passiver Photonendetektor. Das in der Wellenlänge verschobene Licht wird durch Totalreflexion, zu kleinen PMTs an beiden Enden geleitet. Die Auswahl dieses Designs reduziert die Kosten und verbessert das Signal-Rausch-Verhältnis wesentlich, möglicherweise können mit dieser Lösung extragalaktische Supernova in zukünftigen Detektoren beobachtet werden. Als eine Kernkomponente wird die wellenlängenschiebende Röhre ausführlich untersucht. Verschiedene Messaufbauten und Auswertungsmethoden werden entwickelt, um diese im Anschluss zu untersuchen und zu bewerten. Iterative Verbesserungen der Materialien und des Farbauftrageverfahren als auch Messmethoden, resultieren in einer kombinierten Einfang-, Wellenlängenschiebe- und Transporteffizienz von 28,1 +/- 5,4 % der Röhre. Ein Model zur Beschreibung des Lichtverhaltens in der Röhre wird entwickelt um eine Diskrepanz zwischen Theorie und Messung zu untersuchen. Die Kombination zwischen Messung und Model, bestätigt die Aussagekraft des Models und zeigt, dass ein Großteil der Verluste beim Lichttransport zustande kommen. Darüber hinaus werden die physikalischen Eigenschaften des WOM in die IceCube Simulationsumgebung eingebaut. Der Vergleich zu einem Konkurrenzmodul zeigt eine Überlegenheit des WOM um den Faktor 1,05 +/- 0,07. Es werden Vorschläge und Ausblicke für Verbesserungen der Leistungsfähigkeit des WOMs gegeben.
The IceCube Neutrino Observatory is an in ice neutrino detector located at the geographic South Pole. In IceCube neutrinos are detected via Cherenkov light produced by secondary particles in neutrino interactions. For the upgraded detector IceCube-Gen2, new and improved light detectors are sought-after. This work describes the development of one of those light detectors based on a novel combination of wavelength-shifting and light-guiding technology. The detector named the Wavelength-shifting Optical Module (WOM) utilizes a large transparent tube, coated with wavelength-shifting paint as a passive photon detector. The wavelength-shifted light is guided via total internal reflection towards small active light detectors, at each end of the tube. This design reduces costs and improves the signal to noise ratio significantly, thereby potentially enabling extragalactic supernova detections in future detectors. As a core component, the wavelength-shifting tube is extensively investigated. Different measurement setups and evaluation techniques are developed and investigated. Iterative improvement of materials and coating techniques as well as measurement methods currently result in a combined photon capture, shift and transport efficiency of 28.1 +/- 5.4 % for the tube. Those results contrast the theoretical maximum of 74.5 %. A model is developed to describe the light propagation and loss processes in the tube and to understand the discrepancies between theory and measurement. The combination of the measurements with the model, validate the descriptive qualities of the model and show that most of the light is lost during the light propagation in the tube. Additionally, the physical properties of the WOM are included in the IceCube simulation framework. A comparison to a competing module showed that the WOM outperforms by a factor of 1.05 +/- 0.07 in photon detection numbers. Where applicable, suggestions and outlooks are given to enhance the performance of the WOM.

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Russell, Paul Floyd. "Reflections: Light and Structure in Religious Architecture." Thesis, Virginia Tech, 1993. http://hdl.handle.net/10919/34437.

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Light is the most sacred phenomenon and the presence of it in a place of worship is the greatest manifestation of God himself. Man can manufacture all the building materials needed to errect the greatest of structures, but only God can fill it with the light of the sun and make the materials come alive. Through the interplay of light and structure the building can seem to be alive. Through the proper execution of structure and material the building can sculpt light and define the time of day and season of year. This then became the genesis of the project; to sculpt light through natural materials and structure in order to bring glory to the creator and provide a sacred retreat for the weary, a rich interplay of light and material coming together to create a worshipful experience.
Master of Architecture

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Noureddine, Farid. "Vision tridimensionnelle panoramique par telemetrie." Rennes, INSA, 1987. http://www.theses.fr/1987ISAR0008.

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Realisation d'un theoreme a triangulation active. Etude des phenomenes qui interviennent dans le processus de reflexion de la lumiere sur des interfaces air-matiere. Realisation modulaire de la structure microinformatique batie autour d'un microordinateur de type pc. Amelioration des performances du systeme par couplage a un telemetre ultrasonore

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Lišková, Nela. "Termální lázně Yverdon, pět smyslů v architektuře." Master's thesis, Vysoké učení technické v Brně. Fakulta architektury, 2015. http://www.nusl.cz/ntk/nusl-216150.

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The spa area is located in western Switzerland in Yverdon-les-Bains, which extends along the southern shores of Lake Neuchâtel. The aim was to replace the current Spa complex which capacity and operationally not meet today's requirements and also to increase capacity accommodation in the form of hotel. New spa complex is placed as solitaire in the area between the spa parks which creates fluent transition between them. Spa function is divided into multiple objects that have their own character, but which in their complexity creates one house. These objects "float" on the surface of the water, unites them and divides its operations at the same time.

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Brobeck, Caroline, and Elin Westblom. "Solblockerande textilier : Optimering av solskydd." Thesis, Högskolan i Borås, Akademin för textil, teknik och ekonomi, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-22094.

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extilindustrin måste ständigt söka nya alternativ inom beläggningar och laminering för att minska den skadliga miljöpåverkan. En fråga som uppkommit är om beläggningar används i större utsträckning än vad som egentligen behövs. Denna kandidatuppsats har skrivits i samarbete med Artex AB och kretsar kring ett befintligt solskydd och solens ljusspektrum som består av strålar mellan 320–2500 nm. Material som bestrålas kan antingen absorbera, reflektera eller transmittera dessa strålar. Strålarnas alternativa vägar adderat med varandra blir alltid hundra procent, vilket innebär att genom att öka den reflekterande förmågan minskas de andra två tillstånden. I denna studie granskas den totala reflekterande förmågan av ljusspektrumet hos textila material som i sin tur beror på många olika faktorer. Det undersöks även om det är ett steg i fel riktning att använda sig av beläggningar för att nå ett bättre högreflekterande material. Detta även för att minska miljöbelastningen. Eftersom beläggningar generellt förstyvar material är detta kontraproduktivt när man vill bibehålla följsamheten hos en tygvara, vilket är avgörande för denna typ av produkt. Skrynkelheten går nämligen hand i hand med tygvarans då stumma yta. Detta projekt fokuserar på solskydd som ska användas inifrån en bil. Syftet med studien var alltså att undersöka om en obelagd vit och tät tygvara kan uppnå tillräcklig funktion för ett solskydd innanför en bil. I experimenten användes fyra olika tygvaror med olika strukturer i bindningarna för att göra en så omfattande studie som möjligt. Dessa fyra var: en satin, en varptrikå och två stycken tvåskaft, varav den ena glesare och mer matt än den andra. Respektive tygvara beströks med ett färgpigment för att analysera om kombinationen mellan reflektion och elastisk potential var möjlig. Tester som genomförts i denna undersökning var: bestämning av färghärdighet, total reflektion, ljustransmittansmätning och ett egenkomponerat skrynkeltest. Vidare granskades dess skillnader för att undersöka om ett vitt material kunde ge en bättre totalreflektion, men även för att bevisa att en tygvaras konstruktion kan erhålla följsamheten även om en beläggning är nödvändig. Mätvärdena granskades för att sedan jämföra, först med varandra och sedan mot ett referensprov som kommer från en befintlig produkt som författarna fick att tillgå från Artex AB. En trikåvaras elastiska förmåga visade sig kunna bibehållas trots ett belagt ytskikt, och visade även på bra totalreflektion. Denna varptrikå uppvisade, tillsammans med satinen, på bra totalreflektion då de var obelagda och hade god följsamhet. I test om totalreflektion visades det att en vit tät tygvara reflekterade större procent än en belagd tygvara i det synliga ljusets spektrum. För att kunna dra slutsatser om ett vitt obelagt tyg med dessa konstruktioner (satin och varptrikå) hade varit bättre för ett solskydd hade vidare undrsökningar behövts göras. Detta för att se hur mycket av den totala reaktionen som är diffus respektive spekulär
The textile industry must always find ways to reinvent itself and look for alternative options, as the coating and lamination industries are vital for a better environment. A question that needs answering is if coating on textiles are used more than needed. This bachelor thesis is written in cooperation with Artex AB and revolves around the suns light spectrum that consists of rays of 320 to 2500 nm. Materials that irradiate can either absorb, reflect or transmit these wavelengths. The rays alternative routes added with each other is always one hundred percent, which means that through increasing the reflecting capacity the other two will decrease. The most interesting part of this study, was to examine the ability of the light spectrum for material, and take in to consideration it’s construction, structure and color. Textile materials are often coated to add qualities and, in this case, to increase reflecting quality. This study is trying to prove, that it's a step in the wrong direction when it comes to the functionality of a sunshade product and for a reduced impact on the environment. As coating generally stiffens materials it’s contuerproductive with regards to keeping the resilience for the fabric, which is decisive for this type of product. The wrinkles go hand in hand with the fabrics coated surface. Since this project focuses on an existing sunshade product that will be used inside of a car, the heat radiation and the undulations within a certain wavelength that requires reflection will be focused on. The purpose with the study was to examine if an uncoated white fabric can achieve the same function in a sunshade as the current fabric in the product. In the experiments, four fabrics with different structures were used to complete such a comprehensive study as possible. These four fabrics were: one satin, one warp knitted and two plain weave, where one of them was more faint and sparse than the other. Each fabric was coated with a color pigment to analyze the possibilities of a high reflective material that still has elastic potential. The tests that were made was: determination of color fastness, total reflection, light transmit and a wrinkle test. Further on these differences were reviewed, and then concluded that the coating, in hope of increasing the reflection, is negligible. But also, to prove that a fabrics construction can keep its resilience even with a coated surface. These values have been reviewed and then compared with each other and against a reference fabric that the writers took part of from Artex AB. A warp knitted fabric was able to maintain its elastic ability regardless of a coated surface, and also shows good total reflection. This warp knitted fabric showed, together with the satin, good total reflection when they were uncoated and had good resilience. In this test for total reflection, it was proven that a white dense fabric reflects better than a coated fabric in the visible spectra of light. To be able to conclude if a white uncoated fabric with these constructions (satin and warp knitting) would be more useful for a sunshade, further studies had to be made, to see how much of the total reaction that is diffuse and specular.

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Mikulica, Tomáš. "Light Propagation Volumes." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2015. http://www.nusl.cz/ntk/nusl-234902.

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This thesis deals with problem of computation of global illumination in real-time. Two methods are described. Namely Reflective Shadow Maps and Light Propagation Volumes. The first of them deals with the problem by using extended Shadow Mapping algorithm. The second one uses scene embedded into a 3D grid together with Spherical harmonics to compute light propagation in the scene. Furthermore this thesis contains results of measurement of the rendering speed of the Light Propagation Volumes algorithm with various settings on several machines. Quality of the resulting output of the algorithm is also evaluated.

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Lin, Yi-lung, and 林義隆. "Innovative Back Light Unit Design via Specular Reflection." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/px3mgg.

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碩士
國立臺灣科技大學
電子工程系
94
Display is among the most important in the nowadays significant opto-electric industry. Because the liquid crystal is not self-illuminated, it needs an outer light source to operate. Therefore, BLU is the most important part in LCD display and it had been developed several type of BLU carter to demand for market. BLU (Back Light Unit) plays an important role in display. Most of edge lighting BLUs use dot patterns or similar ways to gain uniformity via scattering. In this article, we use mirrors to achieve uniformity. Mirrors reduce the energy loss of source and easier to analyze. In this article, we employ the CCFL for light source of edge lighting BLU, and we use the specular reflection instead of dot patterns for uniformity. This method reduces the energy loss and is easier to analyze. Although parameters (relative position,θ…) adjusting is necessary, the proposed system is suitable for any reflector. As long as the reflected rays are concurrent, the proposal design is independent of reflectors shape and will achieve more uniformity and reduce energy loss.

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Chang, Ruei-Yu, and 張瑞宇. "Fully Convolutional Networks Based Reflection Separation for Light Field Images." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/k6m8qh.

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碩士
國立中央大學
通訊工程學系
107
Existing reflection separation schemes designed for multi-view images cannot be applied to light filed images due to the dense light fields with narrow baselines. In order to improve accuracy of the reconstructed background (i.e., the transmitted layer), most light field data based reflection separation schemes estimate a disparity map before reflection separation. Different from previous work, this thesis uses the existing EPINET based on disparity estimation of light field image without reflection, and separates the mixed light field image of weak reflection. At the training stage, the network takes multi-view images stacks along principle directions of light field data as inputs, and significant convolution features of the background layer are learned in an end-to-end manner. Then the FCN learns to predict pixel-wise gray-scale values of the background layer of the central view. Our experimental results show that the background layer can be reconstructed effectively by using EPINET and the mixed light field image dataset proposed in this thesis.

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Bennett, Agatha Karen. "The design of anti-reflective coatings for a quantum cascade laser emitting light in the mid-infrared range." 2013. http://hdl.handle.net/2152/22627.

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Quantum cascade lasers (QCL) are semiconductor lasers that emit radiation in the mid-infrared to the terahertz (THz) range. External cavity quantum cascade lasers are broadly tunable mid-infrared and even THz laser sources that have a wide variety of applications in spectroscopy, sensing, imaging and other areas. Anti-reflection (AR) coatings, when applied on the laser facet reduce parasitic lasing, increase spectrum purity and tuning range, are crucial for good performance of external cavity systems. This report describes the process of determining the thickness of a double layer AR coating, applying the coatings to a quantum cascade laser and testing its reflectivity in the mid-infrared range. We determined the thickness of each layer of the AR coatings by building a propagation matrix model using Mathematica. We applied the coatings of Al2O3 and ZnSe using an Electron Beam Physical Vapor Deposition and a Sputtering Deposition system. Finally we tested the reflectivity of the laser by measuring a change in threshold current. The initial reflectivity of 30% was reduced to 7.7% with the addition of the AR coatings.
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Dissertations / Theses on the topic 'Light reflection'

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