Дисертації з теми "Optical characteristic"
Щоб переглянути інші типи публікацій з цієї теми, перейдіть за посиланням: Optical characteristic.
Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями
Ознайомтеся з топ-50 дисертацій для дослідження на тему "Optical characteristic".
Біля кожної праці в переліку літератури доступна кнопка «Додати до бібліографії». Скористайтеся нею – і ми автоматично оформимо бібліографічне посилання на обрану працю в потрібному вам стилі цитування: APA, MLA, «Гарвард», «Чикаго», «Ванкувер» тощо.
Також ви можете завантажити повний текст наукової публікації у форматі «.pdf» та прочитати онлайн анотацію до роботи, якщо відповідні параметри наявні в метаданих.
Переглядайте дисертації для різних дисциплін та оформлюйте правильно вашу бібліографію.
1
Li, Hongxia. "Characteristic and sensing properties of near- and mid-Infrared optical fibres." Thesis, Heriot-Watt University, 2009. http://hdl.handle.net/10399/2305.
Анотація:
The work within this thesis investigates the characteristics and sensing properties of novel near- and mid-infrared tellurite and germanate glass fibres and their potential as sensing elements. An asymmetric splicing method for fusion-splicing tellurite and germanate glass fibres to standard silica fibre is demonstrated. The thermal and strain sensing properties of these glass fibres have been studied by analysing the properties of optical fibre Fabry-Perot cavities, which were formed when these high refractive index fibres were spliced to silica fibre, and fibre Bragg gratings. Using fibre F-P interferometer, the normalized thermal sensitivity of tellurite and germanate fibre was measured to be 10.76×10-6/°C and 15.56×10-6/°C respectively, and the normalized strain sensitivity of tellurite and germanate fibre was also measured with values of 0.676×10-6 /με and 0.817×10-6 /με respectively. These results show good agreement with measurements using fibre Bragg gratings in these fibres and are reasonably consistent with the values predicted using available published data for glasses of similar compositions. Tellurite and germanate glass fibres show potential as thermal sensing and load sensing elements compared with silica fibre. The design of an evanescent field gas sensor using tapered germanate fibre for methane gas species detection was investigated and modelled. This model shows the maximum gas cell length (sensing fibre length), detectable gas concentration range, and required gas cell length range for the expected minimum detectable gas concentration of a fibre evanescent field sensor, which gives guidance for the effective gas cell length choosen according to different minimum detectable gas concentration requirement in practise. The investigation of tellurite and germanate glass fibre characteristics and sensing properties offer guidance for their applications in sensing areas.
2
Alexa, Jan. "Využití polarizace světla při filtraci optického signálu." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2018. http://www.nusl.cz/ntk/nusl-376944.
Анотація:
This master thesis deals with the possibility of separation of useful signal from noise using polarization of laser radiation. This thesis is structured into 5 thematic units. The first unit is focused on laser radiation and its properties. The second part contains a deeper focus on the polarization of radiation, its description and the possibilities of measuring the polarization states. The third part of the thesis is devoted to the design of the measuring chains and identification of used elements. Chapter four contains measurement of status of the polarization and its results. The last chapter analyzes particular measuring chains outputs according to their spectral characteristics.
3
Zhou, Ziqi. "Optical and Electrical Properties of Two-Dimensional Materials." Electronic Thesis or Diss., Université de Lorraine, 2021. http://www.theses.fr/2021LORR0141.
Анотація:
Les semi-conducteurs bidimensionnels possèdent de nombreuses propriétés fonctionnelles intéressantes telles qu’électriques, optiques, magnétiques, thermiques etc., qui permettent des applications potentielles notamment dans les dispositifs optoélectroniques ultraminces, transparents et hautement intégrés. La synthèse de nouveaux matériaux bidimensionnels et l’exploration de leurs performances optimales, ainsi que le développement de leurs applications font l’objet d’une intense activité de recherche dans le domaine des matériaux. Cette thèse s’inscrit dans la recherche de nouveaux matériaux bidimensionnels. Un premier axe vise à injecter un courant polarisé en spin dans une structure semi-conductrice bidimensionnelle à base de MoS₂ en vue de contrôler la polarisation de l’émission optique. L’objectif est ici d’élaborer une couche ferromagnétique de CoFeB à aimantation perpendiculaire capable d’injecter des électrons polarisés sans champ magnétique, et sur une grande surface. L’obtention de tels émetteurs optique polarisés doit s’accompagner du développement de photodétecteurs de lumière polarisée à base de matériaux bidimensionnels. C’est l’objet des deux autres axes de cette thèse dans lesquels la photo-détection basée sur les nouveaux semi-conducteur GeAs et des alliages d’éléments des groupes IV-VI tels que SnS et ZnSnS est étudiée. Concernant l’injecteur de spin, on s’intéresse à la fabrication des structures Ta/CoFeB/MgO ayant une large anisotropie magnétique perpendiculairement à l’axe de croissance. Un point important est la réalisation d’un dépôt homogène couvrant toute la surface de la monocouche de MoS₂ sous-jacente, constituant l’émetteur de lumière. En optimisant l’épaisseur de la couche de CoFeB et la température du recuit, on obtient une grande énergie d’anisotropie magnétique perpendiculaire valant 0.975 mJ/m². Par l’analyse des propriétés structurales et chimiques de l’hétérostructure, il est montré que l’insertion de MgO entre le métal ferromagnétique et le matériau bidimensionnel peut efficacement bloquer la diffusion des atomes du ferromagnétique. Il est également montré que la couche de Ta joue un rôle critique « d’absorption » des atomes de B de la couche de CoFeB ce qui induit l’aimantation perpendiculaire. D’après les calculs ab initio, l’épaisseur de MgO peut être ajustée pour modifier la structure de bande de MoS₂, allant d’un gap indirect avec pour une couche de MgO de 7 monocouches (MCs) à un gap direct pour une couche de MgO de 3 MCs. L’effet de proximité introduite par le Fe conduit à une modification de la bande de valence au point Γ pour 3 MCs, alors que celle-ci est négligeable pour 7 MCs. Afin d’obtenir un photodétecteur sensible à la polarisation, on s’intéresse à des cristaux ayant une structure anisotrope. La nature anisotrope intra-planaire du cristal IV-V de GeAs est investiguée par spectrométrie d’absorption résolue en polarisation entre 400 et 2000 nm. Les échantillons nanométriques bidimensionnels obtenus de GeAs démontrent bien un dichroïsme linéaire et une photo-détection sensible à la polarisation. Les ratios dichroïques obtenus par des mesures de photocourant atteignent des valeurs élevées de Ipmax/Ipmin ~ 1.49 à 520 nm et de Ipmax/Ipmin ~ 4.4 à 830 nm. Les cartographies de photo-courant suggèrent que la dépendance du courant avec la polarisation trouve son origine majoritairement aux interfaces électrode/GeAs qui présentent un caractère de type Schottky. Des alliages à base d’éléments des groupes IV-VI tels que SnS et ZnSnS ont également été caractérisés. Il est démontré que SnS présente une mobilité des porteurs valant 37,75 cm²•V⁻¹•S⁻¹ et une photo-réponse de 310,5 A/W. En raison de l’absorption optique anisotrope, le photo-courant est dépendant de la direction de polarisation de la lumière incidente, émise à 808 nm. L’absorption optique en bord d’absorption présente une sensibilité à la polarisation avec le plus haut ratio dichroïque atteint valant 3,06 à 862 nm. [...]Two-dimensional (2D) semiconductor materials exhibit overwhelming electrical, optical, magnetic, thermal and other advantages, which enables their great potential applications in ultra-thin, transparent and highly integrated optoelectronic devices. Searching new two-dimensional materials and exploring their optimal performance, as well as expanding the practical application of two-dimensional materials have been the cores of the researches of two-dimensional materials. This thesis focuses on the vertical magnetic control of the CoFeB film on a large-area single-layer MoS₂ film, which could expand the potential of two-dimensional materials in spin optical detectors, the Polarized Photodetection (anisotropy) based on noval two-dimensional semiconductor GeAs, and the optical characterizations of group IV-VI compounds like SnS and ZnSnS alloys. This paper introduces them in detail through the following three parts: 1. We research the fabrication of the Ta/CoFeB/MgO structures with large perpendicular magnetic anisotropies (PMA) on the full coverage MoS₂ monolayers. By optimizing the thickness of the CoFeB layer and the annealing temperature, a large perpendicular interface anisotropy energy of 0.975 mJ/m² has been obtained at the CoFeB/MgO interface. By analyzing the structural and the chemical properties of the heterostructure, it is found that the insertion of MgO between the ferromagnetic metal (FM) and the 2D material can effectively block the diffusion of the FM atoms into the 2D material, and that the Ta layer plays a critical role to efficiently absorb B atoms from the CoFeB layer to establish the PMA. From the results of ab initio calculations, the MgO thickness can be tuned to modify the MoS₂ band structure, from an indirect bandgap with 7 MLs MgO layers to a direct bandgap with 3 MLs MgO layers. The proximity effect induced by Fe results in a splitting of 10 meV in the valence band at the Γ point of the 3MLs MgO structure while it is negligible for the 7MLs MgO structure. 2. we research the anisotropic optical characterization of a group IV-V compound, Germanium Arsenic (GeAs), with anisotropic monoclinic structure. The in-plane anisotropic optical nature of GeAs crystal is further investigated by the polarization-resolved absorption spectroscopy (400-2000 nm) and the polarization-sensitive photodetectors. In the visible-to-near-infrared range, the 2D GeAs nanoflakes demonstrate the distinct perpendicular optical reversal with an angle of 75~80 degrees on both of the linear dichroism and the polarization-sensitive photodetection. Obvious anisotropic features and the high dichroic ratio of Ipmax/Ipmin ~ 1.49 at 520 nm and Ipmax/Ipmin ~ 4.4 at 830 nm are measured by the polarization-sensitive photodetection. The polarization-dependent photocurrent mapping implied that the polarized photocurrent mainly occurred at the Schottky photodiodes at the electrode/GeAs interface. 3. We research optical characterizations of group-IV-VI compounds like SnS and ZnSnS alloys. SnS nanosheets exhibit carrier mobility of 37.75 cm²·V⁻¹·s⁻¹, photoresponsivity of 310.5 A/W and external quantum efficiency of 8.56×104% at 450 nm. Optical absorption around the absorption edge presents obvious polarization sensitivity with the highest optical absorption dichroic ratio of 3.06 at 862 nm. Due to the anisotropic optical absorption, the polarized photocurrent appears upon the periodic change affected by the polarized direction of the incident light at 808 nm. The ZnSnS alloys combine the advantageous optical parameters of SnS and ZnS₂, which belong to the direct band structure of n-type 2D semiconductors. The carrier mobility of the alloy is 65 cm² V⁻¹ S⁻¹ and the on/off ratio under white-LED illumination is as high as 51
4
Dawei, Jiang. "Electrical and optical characterization of InP nanowire-based photodetectors." Thesis, Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-25733.
Анотація:
This thesis deals with electrical and optical characterization of p+i–n+ nanowire-based photodetectors/solar cells. I have investigated their I-V performance and found that all of them exhibit a clear rectifying behavior with an ideality factor around 2.2 at 300K. used Fourier transform infrared spectroscopy to extract their optical properties. From the spectrally resolved photocurrent data, I conclude that the main photocurrent is generated in the i-segment of the nanowire (NW) p-i-n junctions, with negligible contribution from the substrate. I also used a C-V technique to investigate the impurity/doping profiles of the NW p+-i-n+ junction. The technique has been widely used for investigations of doping profiles in planar p-n junctions, in particular with one terminal (n or p) highly doped. To verify the accuracy of the technique, I also used a planar Schottky sample with an already known doping profile for a test experiment. The result is very similar to the actual data. When we used the technique to investigate the doping level in the NWs photodetectors grown on InP substrates, the results show a very high capacitance above 800pF which most likely is due to the influence of the parasitic capacitance from the insulating layer of SiO2. Thus, a new sample design is required to investigate the doping profiles of NWs.
5
Mourka, Areti. "Probing the modal characteristics of novel beam shapes." Thesis, University of St Andrews, 2014. http://hdl.handle.net/10023/4287.
Анотація:
In this thesis, an investigation into the modal characteristics of novel beam shapes is presented. Sculpting the phase profile of a Gaussian beam can result in the generation of a beam with unique properties. Described in this thesis are Laguerre-Gaussian (LG), Hermite-Gaussian (HG) and Bessel beams (BBs). The diffraction of LG beam modes from a triangular aperture is explored and this effect can be used for the efficient measurement of the azimuthal mode index l that indicates the number of multiples of 2π of phase changes that the field displays around one circumference of the optical axis. In this study, only LG beams with zero radial mode index p, with p + 1 denoting the number of bright high intensity concentric rings around the optical axis, were considered. Then, a powerful approach to simultaneously determine both mode indices of a pure LG beam using the principal component analysis (PCA) algorithm on the observed far-field diffraction patterns was demonstrated. Owing to PCA algorithm, the shape of the diffracting element used to measure the mode indices is in fact of little importance and the crucial step is ‘training' any diffracting optical system and transforming the observed far-field diffraction patterns into the uncorrelated variables (principal components). Our PCA method is generic and it was extended to other families of light fields such as HG, Bessel and superposed beams. This reinforces the widespread applicability of this method for various applications. Finally, both theoretically and experimentally investigations using interferometry show the definitive linkage between both the radial and azimuthal mode indices of a partially coherent LG beam and the dislocation rings in the far-field cross-correlation function (CCF).
6
Hetherington, Mandy Jane. "Optical properties and appearance characteristics of foods." Thesis, University of Reading, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.283602.
7
Yang, Zhijun. "Numerical Study on the Characteristics of Metal Insulator Metal Diode Integrated with Spiral Optical Antenna." University of Dayton / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1386242290.
8
Osborne, Robert. "A theoretical study of the propagation characteristics of some optical waveguides by the beam propagation method /." Thesis, McGill University, 1986. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=65992.
9
Eaton, K. "Response characteristics of thin film optical oxygen sensors." Thesis, Swansea University, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.636760.
Анотація:
The development of a simple, semi-reversible, colorimetric oxygen sensor based on the redox chemistry of 2,6-dichloroindophenol in the presence of fructose and tetrabutylammonium hydroxide is described. The sensor is colourless in the absence of oxygen, but gives a strong blue coloration in oxygen at >30 Torr and quantitative analyses are possible between 0 and 50 Torr. The second type of sensor examined is based on the oxygen quenching of luminescence emitted from polymer encapsulated: platinum octaethylporphyrin, palladium octaethylporphyrin or tris(4,7-diphenyl-1,10-phenanthroline) ruthenium (II). Several means of collecting data from such sensors are evaluated. Gated fluorimeters can give erroneous data unless the natural and quenched lifetimes of the lumophores lie in the range 200 μs - 4ms. Several factors affect the oxygen sensitivity of these films including humidity, which depresses the sensitivity by 42% when using ethyl cellulose as the encapsulating matrix and by 14% when using cellulose acetate butyrate. No significant humidity effect is observed when using silicones, polyvinylchloride or polystyrene. The non-linear relationship between quenching efficiency (I0/I or τ0/τ) and partial pressure of oxygen observed in these films was examined and a simple Freuchlich power law shown to fit response data from six sensors which show a 600 fold variation in oxygen sensitivity. The non-linearity is a result of a site distribution in the sensor film and this has been further investigated using initial rate studies and distribution modelling. Such studies indicate that simulated data from a simple uniform distribution in the quenching rate constant (and/or oxygen solubility) gives good fits to experimental decay curves from the six different sensing systems examined. The required model parameters are easily accessible from experimental data and consistent with those calculated for diffusion controlled quenching by oxygen.
10
Garrett, B. "Characteristics of quaternary semiconductor injection lasers : (Optical gain)." Thesis, Cardiff University, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.376548.
11
Lin, Steven Hung-Che. "Optimization of optical characteristics of travelling wave modulators." Thesis, Massachusetts Institute of Technology, 1985. http://hdl.handle.net/1721.1/15299.
Анотація:
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1985.MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING.
Includes bibliographical references.
by Steven Hung-Che Lin.
M.S.
12
Su, Po-Cheng, and 蘇舶丞. "Optical and Electrical Characteristic of Ⅲ-ⅤSolar cell." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/51636414198536955171.
Анотація:
碩士中原大學
物理研究所
100
We report the time dependent current-voltage (I-V) curve of triple junction InGaP/InGaAs/Ge solar cells under irradiation with different wavelength. The time-dependent trap energy and surface trap velocity of defects, and the temperature dependent trap energy in the triple junction solar cell were investigated. A kink effect in I-V curve is observed at low temperature, originating from the defects in the top subcell. In addition, we try to find out the suitable intrinsic layer thickness in the single-junction GaAs solar cell. According to the measurement of conversion efficiencies, the surface recombination velocities, and the carrier escape mechanism , the suitable thickness of intrinsic layer is 5nm in PIN GaAs solar cell.
13
Chang, Hung-Nan, and 陳宏男. "Electro-Optical Characteristic Of Gel-Glass Dispersed Liquid Crystal." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/29879785903946531165.
Анотація:
碩士國立雲林科技大學
工業化學與災害防治研究所碩士班
89
This study deals with the manufacturing conditions for glass dispersed liquid crystals(GDLC) from metal alkoxide,alkoxy silane and liquid crystal mixture.Since these reactants can easily undergo gelation reaction,at a temperature above roomtemperature, they are hydrolyzed by moisture in air and form polycondensation which results in phase separation with liquid crystal E7.After these reactions, a glass film containing the dispersed liquid crystal droplets is formed.This process start with the solution phase going through gel form and finally solidifies into porous net structure which is called glass phase .As liquid crystals are dispersed in the pores of this glass phase,we called it the glass dispersed liquid crystal. In this stuty,we manufactured different liquid crystal droplets size by matrix sol-gel process.When liquid crystal droplets size is small, the transmission is lower,on the other hand, as the droplets size is larger,is directly related transmission is greater.Therefore,we know that liquid crystal droplets size to the transmission. Besides,we addited the different w.t% of titanium ethoxide in this experiment. When the content of titanium ethoxide quanitity is much higher,then the gelation is fast and resulted in the condensation of matrix to liquid crystal droplets.Therefore, we use polyurethane foam that showed 30μm pore after curing and forced the liquid crystal E7 into the pore by permeation to make PDLC.The result showed that the threshold voltage is 5volt,so we can found,the fetter force of matrix to liquid crystal droplets may influence the threshold voltage.So we addited a series of different silicon oil with varing molecular weight into the liquid crystal mixture to soften matrix ,to lubricate the hole of matrix and to decrease fetter force for liquid crystal droplets.The result shows that the threshold voltage of GDLC containing silicion oil is lower the one without silicion oil. We found that the threshold voltage of GDLC containing no silicion oil is 6volt and its contrast ratio is 5.7,while the GDLC that has silicion oil A006 showed a threshold voltage of 4volt, and its contrast radio is 14.2,especially when it contains 70%(w.t) of liquid crystal E7.
14
Lee, Tsan, and 李瓚. "Optical absorption characteristic of (P2O5, B2O3)-ZnO-V2O5 glasses." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/nb499s.
Анотація:
碩士大同大學
材料工程學系(所)
102
Vanadium phosphate and Vanadium Borate glasses, having composition [(P2O5 or B2O3)50(ZnO)1-xV2O5x ], where x= 0,1,3,5 (mol%)were prepared by conventional melt quench method, and investigated by x-ray diffraction (XRD) and inductively coupled plasma spectroscopy (ICP),and UV-Vis-NIR spectrophotometer(200-3000nm). The characteristic of NIR absorption in P2O5 glass system is higher then in B2O3 glass system especially wavelength 800～1200nm.But the characteristic of NIR absorption is the best in P2O5 and B2O3 glass system, I investigated by the X-ray photoelectron spectroscopy (XPS) to prove the results.I found more than one valence state of V ions being present.(V4+&V5+) The V4+%area is larger then the V5+%area in P2O5-B2O3 glass system, the second is P2O5 glass system, the final is B2O3 glass system.
15
Hang-Ching, Wang, and 王漢卿. "The preparation and characteristic study of nonlinear optical polymers." Thesis, 1994. http://ndltd.ncl.edu.tw/handle/53771708102456700009.
Анотація:
碩士國立交通大學
材料科學(工程)研究所
82
The objective of the project is focused on understanding the osition of the photorefractive (PR) polymers and workingrs on the photorefractive properties. There are four primaryin the photorefractive polymers: photoinduced charge generation(CGM)、 charge transporting material (CTM)、PVB binder andr optical chromophore (DR-19), reacted with dianhydride (PMDA)NLO polymer PMDA-DR19.study, the diffraction properties of the samples by the four-waveFWM) technique are measured to characterize the PR properties ofmers. It is interesting to find that the photorefractive n the sites of the this sample. The highest diffractionp and the rise time is almost several hundreds seconds. The pureshows an excellent diffraction efficiency up to 0.01, but the over 1 hour
16
Wang, Chuan-Chun, and 王傳均. "Static Light Scattering Characteristic of Injection Molded Optical Lenses." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/hz2can.
Анотація:
碩士國立交通大學
機械工程系所
107
Optical lenses quality in smart phones is depending on the refractive index and transparency of the used material. Amorphous polymer materials may contain short-range structures with size between several and tens of nanometers. Short-range structures cause inhomogeneous refractive indices and local density in optical lenses, leading to undesirable imaging. This work aims to build a static light scattering system, and investigate the scattering characteristic of injection molded optical lenses. Polymethyl methacrylate (PMMA) plano-convex lenses are formed via injection molding. Two visible polarized light sources(red and purple laser) are then injected into measuring points to observe scattering behavior of these optical lenses. Refractive index matching fluid is added as appropriate. Experimental results show that polymer optical lenses exhibit local density fluctuation. A moderate to strong positive relationship between static light scattering strength and local density is observed when the experiment is performed in air. A weak relationship is observed when performing the experiment with refractive index matching fluid, because of remaining machinery mark on the container. Refractive index matching fluid can decrease the influence of surface roughness within static light scattering system, but does not eliminate it. Purple light is more suitable than red light for static light scattering method. This work constructs a static light scattering system and uses two kinds of visible laser to investigate the scattering characteristic of injection molded optical lenses. Furthermore, this investigation discusses the relationship between static light scattering strength and local density. This work can be applied as a reference of further studies of static light scattering examination.
17
Jia-Guei, Xu. "Optical characteristic of Si/SiGe heterostructure with strain in Si." 2006. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0001-1707200616223500.
18
Chien, Y. C., and 簡淵基. "Characteristic of CrON for Optical Superlattices Attenuated Phase Shifting Mask." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/97039041316243825522.
Анотація:
碩士大同大學
材料工程研究所
89
The growth of the semiconductor industry is driven by steady advances in microlithography. Lithography is the key enabler of the semiconductor industry. The mask in lithography is the heart of the resulting image on the semiconductor wafer. APSM is an approach that employs phase and interference to provide much sharper imager and improve resolution. It’s could be provide cost effect limits near 0.1 . This experiment was using RF magnetic sputter to deposit chromium oxide-nitride APSM film. Transmittance, reflection, refraction index, and extinction coefficient properties of oxide-nitride and nitride films are determined by the variations of argon, nitrogen, and oxygen flow rate and different deposited power in deposition processes. Then looking for the suitable conditions to satisfy the optical property requirement of APSM. From experiment results it could be found that the reaction of Cr, O, and N atoms were better at the lower power. And deposited chromium oxide rate was higher as the flow increases. We could get that optical properties of n and k was above the optical requirement range of APSM. So chromium nitride and chromium oxide-nitride films could be used one of superlattice APSM film. After the chemical durability test, the transmittance variations of the films increase less than 1%, the chromium nitride and chromium oxide-nitride films have high corrosion resist. It could be proved that the films have a little conductibility.
19
Lai, Ming-Hui, and 賴明輝. "Analysis of Optical Characteristic of Back Light Module in LCD." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/535k58.
Анотація:
碩士崑山科技大學
機械工程研究所
96
Based on the popularization and future market for LCD, the optical research of backlight modules were generally or extensively developed in academics. And the uniform distribution of brightness is the key-point of investigation. Most studies were aimed in dot patterns on Light Guide Plate （LGP）, and only few studies focused on V-Cut patterns . At present, to enhance and improve optical characteristics of the Liquid Crystal Display （LCD） has graduate become vital. We understood from the relative researches that the change design of microstructure on the light guide plate affect directly to the optical characteristic. Thus, through the simulations by optical analysis, the better efficiency of microstructure design can be obtained. The design of V-Cut patterns on LGP surface related to the distribution of brightness are studied in this investigation. We can obtain the distribution diagram of brightness from the simulation results. The angle（θ）, pitch（P）, depth（D） and space（S） of V-Cut pattern are changed in experiment. By comparing of the distribution of brightness for dot pattern and V-Cut pattern , the results show that whatever angle of V-Cut changed, the larger the pitch of V-Cut larger , the more uniform whole distribution of brightness and the lower brightness will be obtained ; the brightness of saw-like micro-structure with front slope is lower than that of back slope type ; but the saw-like micro-structure with front slope is more uniform；phenomena of light centralization on in-light side for back slope type is more severed than that of front slope type. The present results provide better microstructure design of the BLM for LCD light guide plate with microstructure.
20
Chen, Pai-Chiang, and 陳柏強. "The characteristic investigation of fiber optical communication systems and devices." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/75296158409019523991.
Анотація:
碩士正修科技大學
電子工程研究所
96
This study uses Lightwave Polarization Analyzer as the primary apparatus and Tunable Laser Source, Distributed Feed-Back Laser Diode (DFB-LD), and Fabry-Perot Laser Diode (FP-LD) as input sides, of which the components include Dispersion Compensation Fiber, Coupler, Isolator, and fiber optics of different lengths for parts to be tested, for their Degree of Polarization (DOP) and Polarization Modal Dispersion (PMD). It is found that length is a concern; as the length increases, the polarization of FP-LD at 1550nm wavelength decreases from 100% to 91%. The PMDs of 25Km, 50Km and 75Km fiber optics are 0.4ps, 0.8 ps, and 1.2 ps, respectively, suggesting that the higher PMD is, the longer the length is. In addition, when measuring with Dispersion Compensation Fiber, the Dispersion Compensation effect is found in the long wavelength (L-band：1570 ~ 1610 nm) that the PMD decreases from 0.4ps to 0.1ps at 1585nm wavelength. Polarization Dependent Loss (PDL) is also explored for the impact of its features on the parts to be tested. Among the 10/90 coupler, 30/70 coupler, and 50/50 coupler, the 30/70 coupler has the least PDL at 0.05dB. A depolarization experiment achieves depolarization result by using an active Polarization Controller or an assembly of passive couplers. When the polarization controller reaches its maximum rotational speed at 8 rpm, it provides 60% of depolarization. The higher the number of couplers is in the assembly, the higher depolarization is achieved. This study uses an assembly consisting of 5 couplers to achieve the optimal polarization of 6.8%.
21
chen, cheng-chien, and 陳正健. "The study of optical characteristic for white light LED package." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/56463869909563489034.
Анотація:
碩士國立中央大學
光電科學研究所
96
In this thesis, we study the optical model to describe the YAG powder as he yellow phosphor in white light LEDs with GaN chips. We apply Monte-Carlo ray tracing and volume Mie scattering to simulate the blue light and re-generated yellow light in the phosphor powder. We first record the position-dependent absorption of the blue lights and transfer into the yellow lights. Accordingly, we can describe the generation of white lights by the phosphor-based LED. Through the comparison between the experimental measurement and simulation, we successfully build up the optical model of YAG phosphors. Finally, we apply the model to the design of LED package for obtaining accurate light output and color behavior.
22
Xu, Jia-Guei, and 許家桂. "Optical characteristic of Si/SiGe heterostructure with strain in Si." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/80648370903690088097.
Анотація:
碩士國立臺灣大學
電子工程學研究所
94
Abstract Silicon/silicon germanium (Si/SiGe) heterostructures with strain presented in the Si layer has attracted great attention in recent years due to its high mobility in the channel of Metal Oxide Semiconductor Field Effect Transistor (MOSFET). The structure has been employed in optoelectronic devices. Intensive research has been performed in concerning the transport properties of the heterostructure. Nevertheless, the band profile has been less investigated. In this thesis, we report photoluminescence on SiGe/Si with strained presented in the Si layer. Exciton in quantum wells is observed in our measurement. These features reflect the band profile of strained Si. From the analysis, the band alignment of the system is determined. This thesis is organized as four chapters described as followings: Chapter 1: the growth technique of Molecular Beam Epitaxy (MBE) is illustrated. The mechanism of high temperature buffer and low temperature buffer is described. The band structure of both silicon and germanium are introduced briefly. Silicon and germanium are both indirect bandgap materials, and are illustrated by dispersion relation figures and constant energy surface figures. States of electrons and holes in k space can be known easily. Chapter 2: the strain effect, band alignment of Si/SiGe heterostructures, Raman scattering, X-ray diffraction, Transfer Matrix method, and exciton are explained. The content of this chapter is helpful to analyze band structures and understand exciton transitions. Chapter 3: PL measurement is explained briefly, and PL experimental instrument setup is illustrated. In PL spectra, there are dislocation lines (D1, D2, D3, and D4) and phonon lines (no phonon line, TA phonon line, and TO phonon line). They can be measured in the PL experiments. Chapter 4: Exciton transition in the quantum wells are found in PL spectra. The band diagrams of the samples are plotted. The quantized energy levels in the quantum wells are solved by Transfer Matrix method. The experimental data and theoretical analysis are compared. Finally, the diamagnetic shift of exciton transition and which band transition (delta2-hh or delta4-hh) are discussed.
23
Sheng-Shuan, Wu, and 吳昇栓. "The characteristic research of holographic optical element with silver halide." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/09616736268935509105.
Анотація:
碩士中華技術學院
機電光工程研究所碩士班
96
This research uses the He-Ne laser beam and the splitter to obtain two waves. One is a plane wave, and the other is the spherical wave. Both waves are interfered by a silver halide film. The interferometric zone plate is obtained after developing and drying. By using the same principle and changing waveform, the generalized zone plate and extended zone plate are obtained. The focal length of the developed hologram zone plate is obtained by calculation and reconstruction. The zone plate is the essential of holographic optical element (HOE). This study is a survey of the characteristics, technology and applications of HOEs. We also use an aberration and dispersion system to exam the quality of HOEs. Although it is simple and low cost, it is reliable. With this aberration analytical model, better HOEs can be obtained. This system may also be used to exam other optical elements.
24
楊家強. "The Structure Design and Optical Characteristic Analysis of LED reflector." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/65994696396440502516.
Анотація:
碩士明新科技大學
電機工程研究所
98
LED lighting has been a really popular topic and most people believe that it will be able to replace the traditional lighting in the near future. However, it still requires lots of improvement and lighting efficiency (lm/W) is the most critical factor, base board or re-flector lead frame is one of the key components. In fact, different LEDs with various angle design and light curve will result significant differently in light efficiency. In order to reduce the light loss and improve the luminous efficiency of the reflector, we need to increase the reflection of the optics; the lead frame reflector is definitely the key factor of the luminous intensity. In this study, the design of a gradient reflector will depend heavily on the effi-ciency of optics. The main purpose is to replace the second optical design with a fine primary optics. Therefore, we simulated the gradient reflectors and chose optimization based on the actual modeling and measurements. Furthermore, we also used TracePro model to verify the simulation and the actual differences in luminous efficiency.
25
Chen, Wei-Di, and 陳偉迪. "Optical Characteristic and Reliability Analysis of Thin Film Solar Cell." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/40520999571816146921.
Анотація:
碩士臺灣大學
電子工程學研究所
98
In this thesis, the optical characteristic, reliability of thin film amorphous based solar cells and reverse engineering of commercial Sharp and Kaneka thin film micromorph (α-Si/μc-Si) tandem solar cells from Sharp and Kaneka are discussed. According to the outdoor measurement results, we find that VOC decreases and ISC increases with increasing temperature and FF drops with increasing irradiance due to the self-bias effect of shunt resistance. We also find that the shadow effect of solar cell is not so serious when the solar cells in module are in parallel first and then in series from outdoor measurement and simulation results. We setup the external quantum efficiency (EQE) measurement system to know the wavelength dependent absorbing ability of the solar cell so that we can calculate the equivalent JSC from EQE and light source spectra and the equivalent thickness from the fringe shapes of EQE spectrum. Finally, we measure the reliability of micromorph (α-Si/μc-Si) tandem solar cell form Sharp. We find that the efficiency degraded degrade relatively ~ 10% from 10.08% to 9.088% by light soaking for 3.5 days, and then keep in stable. The JSC of the degraded solar cell can be fully recovered to initial value with a reverse bias voltage -1.0V and 5X suns light illumination in 30 minutes.
26
Lin, Wen-Yao, and 林文堯. "Crystal growth and optical characteristic of SnX (X = S, Se)." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/ndhs3g.
Анотація:
碩士國立臺灣科技大學
電子工程系
105
IV-VI compound semiconductors tin monosulfide and tin monoselenide have been grown by chemical vapor transport (CVT) method using I2 as a transport agent. Detailed characterization of the materials were carried out by using energy-dispersive X-ray spectroscopy (EDS) , X-ray diffraction (XRD) , high-resolution transmission electron microscopy (HRTEM) , Raman scattering techniques. The SnX material crystal structure is orthorhombic. Lattice constants of SnS are a = 4.2582Å, b = 3.9860Å, c = 11.4258Å and those of SnSe are a = 4.4499Å, b =4.1569Å, c = 11.6091Å, respectively. According to Raman result, the vibration modes of SnS and SnSe show selection rule for the linearly polarized lights along a and along b axis. The SnX (X=S, Se) shows in-plane anisotropy on the c plane. From the results of transmittance and thermoreflectance, the band gaps and direct interband transitions also show polarization dependency with the linearly polarized lights along a and along b axis. In polarized thermoreflectance (PTR) experiment of SnS, it has a direct band-gap transition at 1.20 eV and an interband transition at 1.616 eV when E//b. For E⊥b, the 1.616 eV transition disappears, the direct-gap transition feature becomes narrow and its energy position shifts to 1.15 eV. Owing to the results of transmittance and thermoreflectance are comparable near band edge, we can infer that SnS is a direct band gap semiconductor. For the PTR result of SnSe, the direct band gap transition is at 0.99 eV and two transitions are at 1.258 eV and 1.374 eV when E//b. For the E⊥b condition, two transitions of 1.258 eV and 1.374 eV disappear, while direct-gap transition become narrow and shifts to 0.94 eV. The SnSe is also a direct band gap semiconductor. For electrical measurements, the conductivity of SnX was determined to be 2.76×10-1 (-cm)-1 for SnS and 1.944×10-1 (-cm)-1 for SnSe, respectively. The surface photovoltage (SPV) measurements of SnS and SnSe also show in-plane anisotropy of the photovoltaic response spectra with E//b and E⊥b conditions. The SnX (X=S, Se) also reveal thermos-electric voltage generated from the samples by hot-probe measurements. From the polarity of thermoelectric voltage, the SnS and SnSe are p-type semiconductors. According to the optical and electrical measurement results, the SnX (X=S, Se) can have both photovoltaic and thermoelectric capability, and which possess the potential for application in the future optoelectronics and energy devices.
27
Shuo-HanWeng and 翁碩韓. "Characteristic Prediction of Antireflection Optical Thin Films by Model Trees." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/s8wf5r.
Анотація:
碩士國立成功大學
工業與資訊管理學系碩士在職專班
106
Modern manufacturing industry of glass coating manufacturing industry is highly competitive, and the decision for efficiently reducing manufacturing costs is important for a company to enhance its competitiveness. The usage of the large amount of data collected from manufacturing processes is not effective, and hence the high production cost is generally caused by the decisions based on personal experience. This study attempts to use the data with plenty of attributes collected from production equipment to build model trees for predicting the characteristics of antireflection optical thin films, including reflection rate and the a and b values of glass color coordinates. The model trees can provide the critical attributes that will affect the characteristics of products. This kind of information can help engineers to set proper manufacturing parameters for reducing setup time and labor cost. The experimental results show that the prediction error of the reflectivity rate is the smallest, and the model tree for each of the three optical characteristics does suggest critical attributes for improving product quality.
28
Banerjee, Swagata. "Propagation characteristic of optical waveguides: development of efficient numerical techniques." Thesis, 1989. http://localhost:8080/iit/handle/2074/4070.
29
Wu, Pin-Hung, and 吳鑌紘. "Electro-optical characteristic of amorphous liquid-crystalBPIII with negative dielectric anisotropies." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/39108502235664727483.
Анотація:
碩士國立中興大學
奈米科學研究所
105
In this thesis, we used a liquid crystal with negative dielectric anisotropy and added chiral dopant with moderate helical twisting power (HTP) to produce BP. The temperature range of amorphous blue phase (BPIII) is about 8.5 ◦C and it covers room temperature. From the experimental results, we observe that, as a horizontal electric field is applied on BPIII, the induced birefringence enhanced as the electric field increasing and hysterisis effect,is free. The response time of BPIII is short in dark state and bright state switching. We also used a liquid crystal with positive dielectric anisotropy and added chiral dopant to produce BP in similar pitch. Comparison with two samples, even if the pitch is similar, the temperature ranges of BP are not similar. The electro-optical characteristics of two samples are similar, but the optical rotations of light areoppositely because the induced slow axes are vertically.
30
Chin-Long, Hung, and 洪金龍. "Preparation and Electro-Optical Characteristic Of Gel-Glass Dispersed Liquid Crystal." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/54470372759806790312.
Анотація:
碩士國立交通大學
材料科學與工程系
88
This thesis is focus on gel-glass liquid crystal dispersed (GDLC) by amino-silicon materials sol-gel process. Following silicon alkoxides have different function groups after their hydrolysis, condensation will have different gelation time, refractive index, resistivity. Owing to refractive index induces contrast ratio that gel-glass materials need to match E7 refractive index for enhance electro-optical performance. The non-active function groups CH3-, C6H5- quantities will impact gelations time, gel-glass structure and response voltage. Cells were made by spin coating, capillary principle, droplets dispersed. Showing spin coating, capillary principle have poor electro-optical performance. 3-(Diethoxymethoxysilyl) propylamine composition offered the gel-glass matrix better flexibility & lower resistivity. Ttanium ethoxide was used successfully to adjust the refractive index and improve the contrast ratio (GDLC-17 C.R.=22.5) . From cell optical microscope structure: the stronger, uniformer structure relative better electro-optical performance (Fig 4-4-1 c). GDLC system matrix are controlled by raw materials compositions, active groups, non-active groups, temperature, humidity…etc.. Here focus materials and active, non-active groups composition that high-line excellent cell gel-glass structure and excellent electro-optical performance.
31
Liu, Wo-Chung, and 劉斡中. "Fabrication and Electro-optical Characteristic Analysis of Metallic Photonic Box Structure." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/22313248277836237353.
Анотація:
碩士國立臺灣大學
光電工程學研究所
93
The evolution of artificial light sources has played an important role in technology development. In ancient times, people had tried to use torch to obtain light in dark. Thomas Alva Edison invented the first lamp in 1878. Since then the mankind has never ceased the intension to invent better artificial illumination sources. With the advancement of VLSI technology, it is no longer impossible to fabricate nano-scale patterns. This leads to the flourish of light emitting diode technology and starts another ``illumination revolution''. In this dissertation, we propose a new illumination structure, named “metallic photonic box”. Such structure is aimed at replacing the current illumination technology to achieve no pollution and high efficiency lighting. We design and fabricate photonic crystal structures with dielectric cube wrapped by metal on silicon wafer. The dimension of the dielectric cube is designed to be 1μm. The structure is successfully made by using standard VLSI process such as exposure, development, dry etch, and evaporation. The cross-section view of the sample is verified by scanning electron microscope. Furthermore, another metallic photonic box structure with dimension around 300nm is also made and measured. We also show the ability of making nano-scale patterns on photoresist through the help of deep UV mask aligner. Finally, an energy transfer structure is proposed. The energy transfer mechanism is not observed before. It is capable of transferring part of the energy of incident 532nm laser to 300nm. The converted signal is proportional to the incident laser energy. In addition, the spectral width is further reduced after the input pumping intensity exceeds 30mW. It is expected that, with the research of such metallic photonic box structure, the artificial illumination will usher in a new era. We hope that future illumination and optical application demands can be fulfilled by this new concept.
32
WENG, YU-HSIN, and 翁玉欣. "The Optical and Material Characteristic Study of MoS2/Cu2O Heterojunction Surface." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/cfg4zw.
Анотація:
碩士國立中正大學
光機電整合工程研究所
105
In this study, the n-type MoS2 monolayer flakes are grown using chemical vapor deposition (CVD), and the p-type Cu2O thin film are grown using Electrochemical deposition method. Transmission electron microscopy (TEM) is used for crystal structure analysis of the grown MoS2 flakes. By observing periodicity diffraction points from corresponding selected area diffraction pattern (SAD) on Cu2O thin film indicates the monocrystalline with our grown sample. Moreover, with the help of Raman spectroscopy, Multiphoton excitation microscope, Atomic force microscope (AFM) and Photoluminescence (PL) measurements we are able to verified the monolayer structure of the MoS2 flakes. After the preliminary process of the grown MoS2 flakes, the sample is then transferred onto Cu2O thin film to finish the p-n heterogeneous structure. The results are verified via Scanning electron microscope (SEM), SHG, and Raman mapping measurements and then conducted PL measurements to analyze the luminous energy gap of the two materials. In the future, electric properties of the sample will be measured and the positive oxide trap state characteristic of the element will be studied. We hope to apply such MoS2 element on biosensors to detect different DNA structures.
33
Hsu, Chin-Yuan, and 徐錦淵. "Optical、Electrical、Thermal characteristic Measurement and analysis of High Power LED." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/17634266281317757329.
Анотація:
碩士國立交通大學
平面顯示技術碩士學位學程
99
In this study, we integrated the integrated sphere, optical emission spectrometer, power supply, thermoelectric cooling (TEC) module, and DAQ card into one system by Labview software. Through the varying approaches, we accomplished the calibration of wavelength, luminous flux, junction temperature, and thermal resistance of LEDs. Besides, we measured and analyzed the thermal resistance of LEDs with different heat slug. This thesis begins with the discussion of basic radiometry, and following by comparison with photometry. Then we defined several useful units from the aspect of colorimetric. We specified the working principle of integrated sphere, optical emission spectrometer and the calibration of emission wavelength, absolute intensity. Next, we introduced three common methods of measuring thermal resistance and contrast them, and we explained why we chose the NIST method. According to the mentioned methods, we developed a system by Labview software which can measure the optical, electrical and thermal characteristics of LEDs at the same time. Finally, we analyzed the thermal characteristics of high power white LEDs under different junction temperature and injection current.
34
Wang, Ting-Lin, and 王廷霖. "Enhance the Performance and Research Characteristic ofNetworks in Optical CDMA systems." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/37113568210244445128.
Анотація:
碩士國立宜蘭大學
電機工程學系碩士班
103
In this thesis, the investigation for improving performance in optical code division multiple access (OCDMA) system is proposed, where the transmission characteristic and throughput analysis are discussed. With the increasing demand of bandwidth in high-speed internetworking OCDMA technique is a preferable way to be as the platform, which has the merits of scalability, asynchronous transmission, security, low cost, and low complexity. Since OCDMA is an interference-limited system, the system performance is dominated by MAI (multiple access interference) and beat noise. We propose three countermeasures to alleviate such adverse impact, which are applied to different system architectures. First of all, the duobinary signaling scheme and LDPC (low density parity check) code are employed to further reduce the error floor. In the second approach, we utilize coded modulation scheme and LDPC code, where the laser chirping effect and fiber dispersion are taken into consideration. Finally, the OHL (optical hard-limiter) and Reed-Solomon code are exploited in unslotted ALOHA network. Our proposed schemes can effectively improve system performance, and can allow more users accommodated in the network.
35
Hsu, Chin-Yao, and 許家耀. "BLOCKING CHARACTERISTIC ANALYSIS OF OPTICAL INTERCONNECTION NETWORK WITH POLARIZATION SELECTIVE ELEMENTS." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/68889369514312651971.
Анотація:
碩士明新科技大學
電子工程研究所
96
This paper is composed by polarization selective elements and electro-optic halfwave plates(EOHWPs). A 4×4 nonblocking optical networks characteristic switch with two stages of polarization selective elements and electro-optic halfwave plates(EOHWPs) is proposed. Because the interconnection lines can pass two differential polarization optical signals, this new structure can not be analyzed by traditional methods. When each electro-optic halfwave plate is transformed to an equivalent optical switch and each polarization selective element is replaced by four interconnection lines, the equivalent structure of this optical switch is the same as a 4×4 double-layer network. Therefore, this 4×4 optical switch supports a strictly nonblocking characteristic. However 8×8, 16×16, 32×32, and N×N networks are rearrangeable nonblocking. In this paper, the blocking characteristic of these networks will be analyzed in detail.
36
Lee, Yaon-Chu, and 李彥助. "Study on optical and electrical characteristic of vertical light emitting diode device." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/k7drsz.
Анотація:
碩士國立交通大學
平面顯示技術碩士學位學程
102
Light-Emitting Diode has the potential to be developed into the mainstream device of cutting edge solid state lighting. Currently, research on LED has its focus on high power and large area (above 1×1 mm2) LED [1]. High power means the heat generated by LED is also of large amount, hence, the research on heat dissipation is also the focus of research. As compared to the traditional sapphire-based LED, for example, the co-planar p type and n type electrodes of Face-up LED and Flip-chip LED, vertical LED has the newest structure, and it also owns better current distribution and heat dissipation capability. Under the same chip size, the electrode masking area is lower, the light-emitting area is the largest, hence, it has the most advantage to be developed into large area (larger than 40 mils) and high power LED. It has both high lumen output and high efficiency, and it is the most crucial optical source technology in the future LED lighting industry. Currently, the package unit of vertical LED or thin GaN LED includes two high temperature bonding processes, one is the substrate transfer process during the chip processing, and the second is the subsequent high temperature die bonding during the packaging process. Double bonding surface is generated by at least two times of high temperature bonding, it not only increases the interface heat resistance, but also reduces packaging yield and reliability. Therefore, innovative vertical LED structure and its manufacturing technology can enhance the photo-thermal property, yield and reliability of the vertical LED, and it will become the key technology of future lighting grade LED optical source. If we take a look from the view point of LED packaging, in addition to providing LED chip protection and electric characteristic, the package’s good thermal conduction and high reliability is also key characteristic of high power LED packaged device. LED wafer-level package (WLP) has its niche today, it is the best technical channel for a semiconductor players to get into the field of solid state lighting industry, hence, it is going to become key crucial technology in the eruption and growth of the next wave solid date lighting.
37
蔡進興. "The Studies of Optical Characteristic for Light Guide Plate Hot Emboss Technology." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/69533798833714484709.
Анотація:
碩士國立彰化師範大學
機電工程學系
97
The TFT-LCD panel can not emit light spontaneously, and then a surface backlight source is needed. The function of light guide plate is to guide light from a light source and control uniformity on the output surface. Because the backlight module is very important key components, many backlight module companies are devoted to develop a brighter and lower power consumption of liquid crystal display. In order to reach the above target of high performance of a light guide plate (LGP) this thesis will present a manufacture processing of LGP called hot emboss method. The results were also compared to the traditional dot pattern. They indicated that the presented methods could reach brighter and uniformity flat panel display by the backlight module.
38
Lin, Tien-Yi, and 林典億. "Optical Characteristic Analysis of Planar Waveguide Devices based on Photonic Crystal Structures." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/ax5569.
Анотація:
碩士國立虎尾科技大學
光電工程系光電與材料科技碩士在職專班
104
We use the photonic crystal design software (Crystal wave) to simulate the design and computational analysis the photonic crystal material filled with organic polymer material (SU8).We also use plane wave method to analyze the photonic crystal structure of its different energy gap diagram, and take advantage of FDTD method to analyze the structure of each light wave conduction behavior. It is coated with a layer of an organic polymer on the SiO2 substrate, and etched to form a photonic crystal air column. (1) Use of an air column distance, Angle, Size to analysis photonic crystal bandgap Changes lightwave conduction . (2) To analyze each shape resonator filter characteristics.
39
Xie, Chi-Kai, and 謝棋凱. "Optical and electrical resistance measurement methods of dynamic characteristic of film thickness." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/qkacuv.
Анотація:
碩士國立虎尾科技大學
機械與機電工程研究所
104
This paper, use the optical multi-beam interference theory to measure oil film thickness, and use the multi-functional potential measured resistance value, explore the relationship between the resistance value of the oil film thickness, carried out by the motor load is applied, whereby the waveform applied to the load, and would like to know the relationship between the dynamic oil film thickness and resistance value , film thickness monitoring precision machinery arising at the time of the operation, in order to facilitate long-term use of mechanical parts and reduce the loss of power and energy generated from the friction. In this study, use the optical interference theory establish a machine to measure the lubricating properties, It sets different slider angles, tangential velocities, load, dynamic load topography parameters to discuss influence of different experimental, and utilizes hydrodynamic lubrication theory to verify its feasibility, after the experiment, in the faster speed the oil film thickness will be larger, the opposite of between the load and oil film thikness, using a resistance measurement of film thickness measurement was higher, the greater the resistance value obtained after explore the relationship between the two regression curve, and get through the regression curve of the relationship between the two, so the impact resistance of the biggest factors for the film thickness, film thickness, the higher the resistance value will be increased. Utilizes dynamic load simulation mechanism consistent film thickness in harsh environments film thickness machine during operation, the experimental verification and Formula Renault, the greater the speed, the faster the film after the degree, load the heavier smaller film thickness, after repeatedly applied load film thickness upward trend, while the greater the speed, the faster rise in amplitude comparison found that the higher the frequency of the appreciation after the film thickness variation converge faster, then slower frequency increased film thickness variation value is less, and the elimination of load and Dynamic load is applied to the film per second rate of change of the high rate of change of the film thickness after the second load is applied.
40
Carvalho, Andreia Filipa Garcia de. "Comprehend the Optical, Morphological, and Electrical Characteristic of Air Processed Polymer Solar Cells." Master's thesis, 2021. http://hdl.handle.net/10362/136008.
Анотація:
Solar energy via photovoltaic (PV) is a promising and freely accessible energy source that has become the main route for managing long term challenges in the energy crisis. Organic solar cells (OSCs) have raised interest in the scientific community due to their enormous potential in solar industry such as mechanical flexibility, exceptional processability, and capability of large-area roll-to-roll (R2R) manufacturing.
In this work, we emphasize to understand the correlation between optical (absorbance and photoluminescence) and morphology properties of air processed photoactive layer, which are prepared at different spin-speeds (800 rpm, 1000 rpm, 1200 rpm, and 1500 rpm) and PC61BM concentration (1.0:0.6, 1.0:0.8 and 1.0:1.0 ratios) and its influence on the performance of OSCs devices. Here, OSCs devices have been fabricated in an inverted bulk heterojunction (BHJ) device configuration viz. sputtered Indium Thin Oxide (sITO)/Zinc oxide (ZnO)/P3HT:PC61BM/ Molybdenum trioxide (MoO3)/Silver (Ag). The sITO, ZnO, MoO3, and Ag were introduced as a transparent cathode electrode, electron transport layer (ETL), hole transport layer (HTL), and an anode electrode, respectively. The blend of regioregular poly(3-hexylthiophene-2,5-diyl) (rrP3HT), donor polymer, and [6,6] phenylC61-butyric acid methyl ester (PC61BM), acceptor molecule, is employed as a photoactive layer in the proposed devices. All the samples (for optical and morphological measurements) and solar cell devices were prepared via spin-coating technique without controlling the atmospheric conditions. A thin interface layer of MoO3 (10 nm, 0.2-0.5 Å/sec) and anode electrode (Ag, ≈ 150 nm, 1.5 Å/sec) were both deposited, sequentially, on the photoactive layer using thermal evaporation with a vacuum of 10-6 Torr. The photovoltaic performance parameters were explored by using current-voltage (J-V) characteristics.
Furthermore, electrochemical impedance spectroscopy (EIS) was used to generate an electrical model for the extraction of charge transport parameters of air processed OSCs devices such as the chemical capacitance (Cμ), effective lifetime (τn), diffusion time (τd) and charge carrier mobility (μ). Additionally, the long-term stability of the produced photovoltaic devices is reported.A energia solar fotovoltaica é uma fonte promissora e acessível de energia que se tornou a rota principal para a gestão dos desafios impostos pela crise energética a longo termo. As Células Solares Orgânicas (CSOs) captaram o interesse da comunidade científica devido ao seu enorme potencial industral como a sua flexibilidade mecânica, o processamento exceptcional e a capacidade de produção roll-to-roll (R2R) a larga escala. Neste trabalho, deu-se ênfase à correlação entre as propriedades óticas (absorbância e fotoluminescência) e morfológicas das camadas activas processadas em atmosfera aberta, as quias preparadas a diferentes spin-speeds (800rpm, 1200rpm, 1500rpm), possuem diferentes concentrações de PC61BM (a 1.0:0.6, 1.0:0.8 e 1.0:1.0 proporções) e a sua influência na performance das CSOs. Aqui, as CSOs foram fabricadas numa configuração de dispositivo invertida baseda no principio de heterojunção (BHJ). O Óxido de Indio Estanho (ITO), preparado pela técnica Sputtering RF, sITO/Óxido de Zinco (ZnO)/P3HT:PC61BM/ Tróxido de molibdénio (MoO3)/Prata (Ag). sITO, ZnO, MoO3, e Ag foram introduzidos como cátodo (electrodo) transparente, camada transportadora de eletrões (ETL), camada de transportadora de buracos (HTL) e ânodo (electrodo), respetivamente. A mistura de regioregular poli (3-hexiltiofeno) (rrP3HT), polímero doador, e [6,6]-fenil-C61-ácido butírivo-metil ester (PC61BM), a molécula aceitadora, foi utilizada como camada ativa nos dispositivos propostos. Todas as amostras (para as avaliações óticas e morfológicas) e as células solares foram preparadas através da técnica de spin-coating , sem controlo das condições atmosféricas. Uma interface fina de MoO3 (10 nm, 0.2-0.5 Å/sec) e um ânodo (elétrodo) (Ag, ≈ 150 nm, 1.5 Å/sec) foram ambos depositados, sequencialmente, na camada activa através da sua evaporação térmica a vácuo de 10-6 Torr. Os parâmetros de performance fotovoltaica foram explorados através das curvas caracteristicas J-V. Além disso, a espectroscopia de impedância eletroquímica (EIS) foi utilizada para gerar um modelo elétrico para a extracção dos parâmetros de transporte de carga de dispositivos solares processados em atmosfera aberta, tais como capacitância química (Cμ), tempo de vida efetivo (τn), tempo de difusão (τd) e mobilidade global (μ). Adicionalmente a estabilidade de longo-termo das células produzidas é reportada.
41
Lin, Chen-Yen, and 林佳彥. "Characteristic Measurement of All Optical Phase Modulation Based On Field-Driven Quantum Wells Waveguide." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/9gct2q.
Анотація:
碩士國立中山大學
光電工程學系研究所
103
Nowadays, the development of fiber communication and cloud technology faces a large challenge due to the saturation of signal bandwidth, intriguing the interests for high speed all-optical signal processing in the near future. All-optical signal modulation can enable high speed operation without using traditional RC circuit limitation, reducing power consumption and increasing the flexibility of management in optical network applications. Through the phase modulation in optical signal processing, usage of optical wave interference could lead to large signal-to-noise ratio, high extinction ratio, and low basic power need. Therefore, it is important to study high efficient phase modulation. In this work, based on quantum confined Stark effect (QCSE), the refractive index- and thus phase- change in quantum well device is studied and used for optical modulation. As an optical power near the bandgap is incident into QW to induce high optical absorption, the built-in electric field from photo-absorption carriers could induce highly nonlinear optical absorption change, thus leading to highly nonlinear optical refractive index change. By exciting another optical wave near the bandgap, the high-efficient phase modulator can thus be expected, leading to all optical modulation. In my experiment, the direct characteristics of electro-to-optical conversion is first used to examine the refractive index change against with electric field. Through the differential phase-shift keyed (DPSK) demodulator, the optical-to-optical (OO) cross phase modulation can be made to analyze and characterize the phase variation in QW device. Using as short as 350-um long active waveguide, 140 degree phase change is demonstrated.
42
Wu, Jung-Ming, and 吳俊旻. "The Study of An Automatic Optical Inspection System for Lens Aberration and Characteristic Measurements." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/26258171254619204881.
Анотація:
碩士逢甲大學
自動控制工程所
96
The analysis of quality verification of a lens module was presented. This system includes image quality verification measurements and the time measurement of an auto focus performance of zooming module. In the image quality measurements for the zoom lens module, in order to replace the present lens measure device for curvature of field and manual adjusting of screen distance. The system utilizes screen equipped on automatic driving system and computer vision technique, along with DLP projection and computer software to capture data from image area by scanning, and then obtains average and threshold values of its pixels. The analysis is based on 8 adjoining points to conduct contractive algorithm between bright spot and dark spot, and automatically measure the figure projected on the screen to be measured and draw real-time measuring results. The inconveniences and errors from traditional manual measurement can be completely solved by this system. When comparing the measured result with that of optics emulating software, the accuracy and time effect of this automatic inspection measurement for lens aberration of spherical aberration and field curvature are significant. Examines quality of the lens, basically utilizes the black white line pairs, analysis its contrast gradient. This system also consists of a screen showing grating-type target variety automatically and a camera to capture the image for analysis. The computer plots the contrast value and obtains the MTF result of the testing camera lens. In the compensation process, a new computation method of grating positioning is used in this research with sub-pixel method. The experimental results, including system calibration, alignment calculation, grating locations, and statistical functions of inspection are presented and evaluated. The speed and accuracy of this imaging system are supported by the available experimental observations. In the time measurement of auto zooming module, to handle the function of zooming performance, we assist a novel method of the time measurement of auto focus of zooming module, and we can provide accurate measurement data in inspection within few minutes by using the subframe technology.
43
Yeh, Chia-Chi, and 葉家齊. "Study on Optical Characteristic of White Light-Emitting-Diodes with Remote and Conformal Phosphor." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/07534169314600223722.
Анотація:
碩士國立交通大學
光電工程學系
100
In this thesis, the phosphor layer of white light-emitting-diodes (LEDs) was systematically investigated. In order to comprehend the optical characteristic of phosphor layer in packages, the emission distribution of phosphor film would be investigated first. In first section, a phosphor film would be manufactured and measured by angular-dependent excitation to obtain the emission distribution of the phosphor film. Through the emission distribution of phosphor film, the emission model of phosphor film could be established. This emission model also agreed with the emission characteristics of remote and conformal phosphor LED. Furthermore, the poor angular-dependent CCT distribution of remote phosphor, caused by the low intensity of blue light at large angle, could be clarified. Second, the cause of poor angular-dependent CCT distribution of remote phosphor was investigated in first part. In order to improve the blue light intensity of remote phosphor at large angle, the patterned structure of remote phosphor was designed. The angular-dependent CCT distribution of remote phosphor could be improved through the window region of patterned structure.
44
Lin, Cian-Yi, and 林千藝. "The Application of Ultra-Violet Optical Laser Induced Fluorescence System on Fuel Characteristic Recognition." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/03058462659399040509.
Анотація:
碩士崑山科技大學
環境工程研究所
102
Abstract In this study, Laser Induced Fluorescence (LIF) tool was employed to detect 45 fuel samples, including Motor Unleaded Gasoline, Automotive Diesel Fuel, Aviation Turbine Fuel JP-8, Marine Residual Fuels, Low Sulfur Boiler Fuel, and their blending mixtures. The outputs of Laser Induced Fluorescence (LIF) detection present fluorescence characteristic spectra and relative percentage of (% RE) fluorescence strength based on sample species and their concentrations. Accordingly, each pure phase fuel possesses a unique and particular fluorescence spectrum. Motor Unleaded Gasoline, Automotive Diesel Fuel and Aviation Turbine Fuel JP-8 spectra are characterized by fluorescence peak at 350 nm wavelength, and their contributions of total fluorescence strength (% RE) are 34%, 35.5% and 84.1%, respectively. Marine Residual Fuel is characterized by fluorescence peaks at 400 nm and 450 nm wavelengths, corresponding with 35.1% and 42.4% contributions of total fluorescence strength (% RE). Low Sulfur Boiler Fuel is characterized by fluorescence peaks at 450 nm and 500 nm wavelengths, corresponding with 45.2% and 42.2% contributions of total fluorescence strength (% RE). Fluorescence Reference Index (FRI) was established through Principal Component Analysis of LIF detection signal data based on 45 fuel samples. FRIs of Low Sulfur Boiler Fuel are recognized as the signal at 350 nm and the ratio of 400 nm/ 350 nm, which are 0.6 and 9.84. FRIs of Aviation Turbine Fuel JP-8 are recognized as the ratios of 350 nm/500 nm and 350 nm/450 nm, which are 59.27 and 33.95. FRIs of Gasoline and Marine Residual Fuels are recognized as the ratios of 450 nm/500 nm and 500 nm/450 nm, which are in the ranges of 2.68 ~ 2.98 and 0.34 ~0.37, respectively. FRIs of Marine Residual Fuels and Automotive Diesel Fuel are recognized as the signals at 450 nm and 500 nm, which are 31.7 and 23.8. By using cluster analysis, 45 fuel samples were classified into three clusters, which sorted light fuel-based samples in the first cluster, Marine Residual Fuels blended samples in the second cluster, and Low Sulfur Boiler Fuel blended samples in the third cluster. By using principal component analysis, spectral data of 45 fuel samples were roughly grouped in three categories, and further precisely graded to six sub-categories. This study demonstrated the feasible application of LIF system to the recognition of fuel characteristics. Comparing with traditional field sampling method, laser induced fluorescence tool can quickly obtain the information of sample characteristics to identify fuel species and to differentiate different manufactures or import sources of fuels.
45
Chen, Ying-Yin, and 陳盈吟. "A study on produce and characteristic in micro-size optical particles of poly(methyl methacrylate)." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/35655917790798540215.
Анотація:
碩士國立勤益科技大學
化工與材料工程系
95
Micro-size optical particles of Poly (methyl methacrylate) were produced at size range of the 1-10μm by dispersion polymerization in an methanol /water mixed-dispersion medium with poly(vinylpyrrolidone) as a steric stabilizer and 2,2'-azobisisobutyronitrile as a radical initiator. The effects of the reaction parameters on the particle size, size distribution, thermal properties and optical properties, such as the cross-linking agent concentration, media solvency (controlled by varying the amount of methanol addition), the concentration of initiator and stabilizer were investigated. The particle size increased with the decrease of the system’s initial solubility parameter and monomer concentration (MeOH/H2O=70/30 wt%). The appropriate increase in stabilizer concentration was a prerequisite for prepared particles without coagulated and/or odd-shaped particles. When concentration of initiator was added into the system, a notably increasingly the particle size and widely particle size distribution. Particle size and size distribution were found to increase with increasing polymerization temperature. On the other hand, the surfeit amount of the cross-linking agent in the reaction leads to agglomerate particles itself. The investigation of the effects of the polymerization parameters also shows that only specific sets of conditions produce particles with the particles size and distribution. In this study, the Tg of the synthesized PMMA is about 116-121°C,which is fairly higher than that of commercial PMMA (Tg=105°C). The synthesized PMMA of 0.005-0.02wt% cross-linking agent (EGDMA) is greater than 120℃, but the higher 0.025wt% of EGDMA shall not measured with Tg. The optical property of particles was characterized employing the UV-Vis and ABBE refractometer. The macro-size optical particles the refractive index of increased with increasing concentration of optical macro-size particles at the 546nm or 589nm. However, the scatter index decreased with increasing amount of macro-size optical particles. When 10mg of macro-size optical particles was dispersed in the methanol, the refractive index at 546nm was found to decrease from 1.3265 to 1.3283 with increasing the particles size from 1.61 to 3.97. In this research, result shows higher of scatter index (550nm) and refractive index (546nm), when the particle size is 1.79um.
46
Lin, Ru-Ling, and 林儒伶. "Electro-Optical Characteristic of Dual-Frequency Liquid Crystal in OCB Cell with Polymer Aligned Material." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/4wmej4.
Анотація:
碩士國立臺北科技大學
光電工程系研究所
97
Optically compensated bend (OCB) mode liquid crystal display (LCD) intrinsically has features of fast response time and wide viewing angle that is suitable for showing high image quality and fast moving picture without blurring. When the conventional OCB cell is driven from initial splay state to operating bend state the need of high transferred energy leads to a long warm up time and high voltage. In order to solve these problems, the OCB cell having high pretilt splay or twist state is developed by using polymer stabilization method (PS). In this experiment, two kinds of curable monomer are mixed together with liquid crystal material and an ac electric field is applied during photo-polymerization process. Recently, bistable LCD has attracted much attention from the concept of low power consumption because the image can be stable without applied voltage and frames do not refresh frequently. In this study, a bistable OCB cell which used dual frequency liquid crystal material is investigated. The electro-optical characteristics of the bistable OCB cells with different mixture concentration and curing voltage is studied.
47
Cheng, Wei-Chih, and 鄭偉志. "Analysis of the Optical Characteristic of Photonic Crystal based on Silicon Substrate with PDMS Pillars." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/y3zwsk.
Анотація:
碩士國立虎尾科技大學
光電與材料科技研究所
103
In this thesis, the photonic crystal design software Crystal Wave ver. 3.2 is used to simulate the silicon-based substrate with etched periodically arranged holes, filled with PDMS material. Plane Wave Expansion method is used to calculate the photonic band gap, then the photonic crystal waveguide and resonant cavity is formed by crystal defects. Simulate the propagation behaviors of light using finite-difference time-domain method. Design the structure of waveguides and to compare the filter characteristics in different structures. By the simulation results, we can find out some filter structure could be suitable in optical communication devices.
48
Chen, Chun-Yu, and 陳君昱. "Exploring the characteristic of optical vortex beam in a self-mode-locked Yb:KGW monolithic laser." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/2w93c5.
Анотація:
碩士國立交通大學
理學院應用科技學程
106
In this thesis, we investigate the formation of high-order transverse mode in a Yb:KGW monolithic laser and observe the structure of the optical vortex converted by a cylindrical lens. We firstly investigate the characteristic of Yb:KGW crystal in the quasi-three-level laser system and the monolithic cavity design. We then explore the output performance and the temporal behavior of the monolithic laser. Optical vortex beam is further generated by a cylindrical lens mode convertor and the vortex structure is examined by a Mach-Zehnder interferometer. Finally, theoretical analysis is carried out to analyze the experimental results. Dual-comb self-mode-locked operation with abundance of transverse pattern along Nm- and Np-axis is experimentally obtained with high-power high-repetition-rate Yb:KGW monolithic laser. We further employ a cylindrical lens mode convertor to generate LG0,2 and LG0,3 mode and the vortex structure is successfully observed through a Mach-Zehnder interferometer. The simulation result corresponds well with the experimental result for the LG0,2 mode.
49
Wu, Shing-Trong, and 吳欣璁. "Studies of electro-optical characteristic of liquid crystal-polymer composites doped with a high dielectric material." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/85966888886488379025.
Анотація:
碩士國立成功大學
物理學系
88
Studies of electro-optical characteristic of liquid crystal-polymer composites doped with a high dielectric material Student： Shing-Trong Wu Advisor： Andy Ying-Guey Fuh Department of Physics, National Cheng Kung University, Tainan ,Taiwan 701, ROC Abstract We work with two kinds of liquid crystal-polymer composite films doped with a material having a high dielectric constant and study their electro-optical effects in this thesis. These include (1) Polymer-Dispersed Liquid Crystal Film (PDLC); (2) Polymer-Stablized Cholesteric Texture (PSCT). Experiments are divided into two parts as follow. (1). We use PDLC film to record holographic grating (HPDLC), then study the relationship between the first-order diffracted beam intensity of the gratings and the driving voltage . Our purpose is to lower the switching voltage of the grating. (2). We fabricate PSCT normal-mode films, then study the relationship between the transmission of the film and its driving voltage. Our purpose is to improve the performance of this display device. The results obtain from the studies of the films’ electro-optical characteristics show that both the PDLC and PSCT films doped with a material having a high dielectric constant have a lower driving (or switching) voltage. The cause of such a reduction is due to the modification of the polymer matrix with the addition of that material that enhances the polymerization rate of the film during curing.
50
Chen, Wei-Zheng, and 陳威整. "Preparation and Characteristic Study of the PMMA/PQ Photopolymer and its Application on Optical Data Storage." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/45897418569218053578.
Анотація:
碩士國立交通大學
材料科學與工程系
87
In this thesis, we synthesize a high optical quality photopolymer for holographic memory. Chemical analyses are performed to study on the recording mechanism. Based on these results, characteristics for holographic data storage are obtained. Then, a volume holographic storage system is constructed using our polymer block. Our samples are prepared by dissolving 9,10-phenenthrenequinone (PQ, up to 0.7%) and initiator azobisisobutyronitrile (AIBN, up to 1.5%) in the purified Methyl methacrylate (MMA) monomer. The solution is poured into different glass flasks to fabricate the samples in a variety of dimensions. The samples with different concentration of AIBN and PQ are then placed in a temperature-controlled chamber at 45℃ for three days to polymerize MMA monomer. Then, the samples are turned into solid blocks. Analyzing of the optical exposed samples by using UV, TGA, GPC, Mass, FT-IR and NMR indicates that in our PMMA/PQ samples, the PQ molecules reacted with MMA monomers one by one. The products contain two different compounds. We have also studies the influence of the concentrations of PQ and AIBN for the holographic recording. The results show that the diffraction efficiency of the grating increases with the concentration of PQ, and increases slightly as that of AIBN increases. However, the increase of the AIBN will reduce the optical transmission of the samples. Based on these results, up to 2.5x2.5x2.5 cm3 PMMA/PQ photopolymer volume with high-optical-quality can be made. We have performed multiple plane wave holograms storage experiments in our PMMA/PQ photopolymer samples to study photo-sensitivity, dynamic range, angular selectivity, exposure schedule and fanning effect. The results show that the dynamic range and the response energy of our polymer increase with the thickness. The angular selectivity decreases with the thickness. In addition, a special exposure schedule is proposed to obtain uniform diffraction efficiency of multiple holograms. Finally, multiple storage of 250 image holograms recorded in a single spot of a 1cm3 sample block using scheduled exposure and 90-degree angle-multiplexing geometry is demonstrated.