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Novel Techniques in Quantum Optics: Confocal Super-Resolution Microscopy Based on a Spatial Mode Sorter and Herriott Cell as an Image-Preserving Delay LineBearne, Katherine Karla Misaye 18 May 2022 (has links)
Breaking Rayleigh’s "curse" and resolving infinitely small spatial separations is one motivation for developing super-resolution in imaging systems. It has been shown that an arbitrarily small distance between two incoherent point sources can be resolved through the use of a spatial mode sorter, by treating it as a parameter estimation problem. However, when extending this method to general objects with many point sources, the added complexity of multi-parameter estimation problems makes resolution of general objects quite challenging. In the first part of this thesis, we propose a new approach to deal with this problem by generalizing the Richardson-Lucy (RL) deconvolution algorithm to accept the outputs from a mode sorter. We simulate the application of this algorithm to an incoherent confocal microscope using a Zernike spatial mode sorter rather than the conventional pinhole. Our method can resolve general scenes with arbitrary geometry. For such spatially incoherent objects, we find that the resolution enhancement of the sorter-based microscopy using the generalized RL algorithm is over 30% higher than the conventional confocal approach using the standard RL algorithm. This method is quite simple and potentially can be used for various applications including fluorescence microscopy. It could also be combined with other super-resolution techniques for enhanced results. The second part of this thesis explores the potential for the Herriott cell to be used as an image-preserving delay line. In quantum imaging, entangled photons are often utilized to take advantage of their spatial and temporal correlations. One photon (“the signal”) interacts with the system to be measured and the other (“the herald”) is used to trigger the detection of the signal. However, for a typical high-sensitivity camera, there is a delay on the order of 20 ns between the trigger and the sensor becoming active allowing for the signal to be recorded. An image-preserving delay line (IPDL) serves to store a photon without distorting the spatial structure and losing the spatial and temporal correlations. It is commonly made with a series of 4f systems to repeatedly image the light field. We propose to use the Herriott cell as an image-preserving delay line. We tested 10 of the lower-order HG modes and found it was able to preserve almost all of them with high fidelities (>90%), with the only exceptions being the largest modes (HG03 and HG30) at the longest delay (7.9 m) where the fidelity was still >86%. In addition to these modes, it was also able to store general images. This application of the Herriott cell affords insights into miniaturizing IPDLs, which tend to occupy a significant amount of space. Overall, these two projects offer novel insight and application to the world of quantum imaging.
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Compressive Transient ImagingSun, Qilin 04 1900 (has links)
High resolution transient/3D imaging technology is of high interest in both scientific research and commercial application. Nowadays, all of the transient imaging methods suffer from low resolution or time consuming mechanical scanning. We proposed a new method based on TCSPC and Compressive Sensing to achieve a high resolution transient imaging with a several seconds capturing process. Picosecond laser sends a serious of equal interval pulse while synchronized SPAD camera's detecting gate window has a precise phase delay at each cycle. After capturing enough points, we are able to make up a whole signal. By inserting a DMD device into the system, we are able to modulate all the frames of data using binary random patterns
to reconstruct a super resolution transient/3D image later. Because the low fill factor of SPAD sensor will make a compressive sensing scenario ill-conditioned, We designed and fabricated a diffractive microlens array. We proposed a new CS reconstruction
algorithm which is able to denoise at the same time for the measurements suffering from Poisson noise. Instead of a single SPAD senor, we chose a SPAD array because it can drastically reduce the requirement for the number of measurements and its
reconstruction time. Further more, it not easy to reconstruct a high resolution image with only one single sensor while for an array, it just needs to reconstruct small patches and a few measurements.
In this thesis, we evaluated the reconstruction methods using both clean measurements and the version corrupted by Poisson noise. The results show how the integration over the layers influence the image quality and our algorithm works well while the measurements suffer from non-trival Poisson noise. It's a breakthrough in the areas of both transient imaging and compressive sensing.
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Co-conception des systemes optiques avec masques de phase pour l'augmentation de la profondeur du champ : evaluation du performance et contribution de la super-résolution / Co-design of optical systems with phase masks for depth of field extension : performance evaluation and contribution of superresolutionFalcon Maimone, Rafael 19 October 2017 (has links)
Les masques de phase sont des dispositifs réfractifs situés généralement au niveau de la pupille d’un système optique pour en modifier la réponse impulsionnelle (PSF en anglais), par une technique habituellement connue sous le nom de codage de front d’onde. Ces masques peuvent être utilisés pour augmenter la profondeur du champ (DoF en anglais) des systèmes d’imagerie sans diminuer la quantité de lumière qui entre dans le système, en produisant une PSF ayant une plus grande invariance à la défocalisation. Cependant, plus le DoF est grand plus l’image acquise est floue et une opération de déconvolution doit alors lui être appliquée. Par conséquent, la conception des masques de phase doit prendre en compte ce traitement pour atteindre le compromis optimal entre invariance de la PSF à la défocalisation et qualité de la déconvolution.. Cette approche de conception conjointe a été introduite par Cathey et Dowski en 1995 et affinée en 2002 pour des masques de phase continus puis généralisée par Robinson et Stork en 2007 pour la correction d’autres aberrations optiques.Dans cette thèse sont abordés les différents aspects de l’optimisation des masques de phase pour l’augmentation du DoF, tels que les critères de performance et la relation entre ces critères et les paramètres des masques. On utilise la « qualité d’image » (IQ en anglais), une méthode basée sur l’écart quadratique moyen définie par Diaz et al., pour la co-conception des divers masques de phase et pour évaluer leur performance. Nous évaluons ensuite la pertinence de ce critère IQ en comparaison d’autres métriques de conception optique, comme par exemple le rapport de Strehl ou la fonction de transfert de modulation (MTF en anglais). Nous nous concentrons en particulier sur les masques de phase annulaires binaires, l’étude de leur performance pour différents cas comme l’augmentation du DoF, la présence d’aberrations ou l’impact du nombre de paramètres d’optimisation.Nous appliquons ensuite les outils d’analyse exploités pour les masques binaires aux masques de phase continus qui apparaissent communément dans la littérature, comme les masques de phase polynomiaux. Nous avons comparé de manière approfondie ces masques entre eux et aux masques binaires, non seulement pour évaluer leurs avantages, mais aussi parce qu’en analysant leurs différences il est possible de comprendre leurs propriétésLes masques de phase fonctionnent comme des filtres passe-bas sur des systèmes limités par la diffraction, réduisant en pratique les phénomènes de repliement spectral. D’un autre côté, la technique de reconstruction connue sous l’appellation de « superresolution » utilise des images d’une même scène perturbées par du repliement de spectre pour augmenter la résolution du système optique original. Les travaux réalisés durant une période de détachement chez le partenaire industriel de la thèse, KLA-Tencor à Louvain, Belgique, illustrent le propos. A la fin du manuscrit nous étudions la pertinence de la combinaison de cette technique avec l’utilisation de masques de phase pour l’augmentation du DoF. / Phase masks are wavefront encoding devices typically situated at the aperture stop of an optical system to engineer its point spread function (PSF) in a technique commonly known as wavefront coding. These masks can be used to extend the depth of field (DoF) of imaging systems without reducing the light throughput by producing a PSF that becomes more invariant to defocus; however, the larger the DoF the more blurred the acquired raw image so that deconvolution has to be applied on the captured images. Thus, the design of the phase masks has to take into account image processing in order to reach the optimal compromise between invariance of PSF to defocus and capacity to deconvolve the image. This joint design approach has been introduced by Cathey and Dowski in 1995 and refined in 2002 for continuous-phase DoF enhancing masks and generalized by Robinson and Stork in 2007 to correct other optical aberrations.In this thesis we study the different aspects of phase mask optimization for DoF extension, such as the different performance criteria and the relation of these criteria with the different mask parameters. We use the so-called image quality (IQ), a mean-square error based criterion defined by Diaz et al., to co-design different phase masks and evaluate their performance. We then compare the relevance of the IQ criterion against other optical design metrics, such as the Strehl ratio, the modulation transfer function (MTF) and others. We focus in particular on the binary annular phase masks, their performance for various conditions, such as the desired DoF range, the number of optimization parameters, presence of aberrations and others.We use then the analysis tools used for the binary phase masks for continuous-phase masks that appear commonly in the literature, such as the polynomial-phase masks. We extensively compare these masks to each other and the binary masks, not only to assess their benefits, but also because by analyzing their differences we can understand their properties.Phase masks function as a low-pass filter on diffraction limited systems, effectively reducing aliasing. On the other hand, the signal processing technique known as superresolution uses several aliased frames of the same scene to enhance the resolution of the final image beyond the sampling resolution of the original optical system. Practical examples come from the works made during a secondment with the industrial partner KLA-Tencor in Leuven, Belgium. At the end of the manuscript we study the relevance of using such a technique alongside phase masks for DoF extension.
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Acoustique des milieux bulleux : applications à la conception de métamatériaux et à la manipulation de bulles / Acoustics of bubbly media : Application to the design of metamaterials and to bubble manipulationLanoy, Maxime 02 December 2016 (has links)
Lorsqu’elle est excitée par une onde ultrasonore, une bulle d’air oscille. Les mouvementsl’interface eau-air entrainent un déplacement local du fluide hôte qui devient lesiège de la propagation d’une onde diffusée. Ce mécanisme très simple est fidèlementdécrit par le formalisme de Rayleigh-Plesset datant du début du siècle dernier. Abasse fréquence, au voisinage de la résonance de Minnaert, les oscillations de la bullepeuvent devenir particulièrement amples et la diffusion extrêmement efficace. Dansun environnement réaliste, les bulles sont présentes en grand nombre et la descriptionse complique sensiblement puisque la propagation résulte de l’interférence entre uneinfinité de séquences de diffusion.Au cours de cette thèse, nous introduirons les modèles de milieux effectifs quipermettent de prédire le comportement de fluides bulleux désordonnés. Après avoirété confrontées aux résultats issus de la simulation numérique, ces théories effectivesnous permettront de concevoir des matériaux désordonnés aux propriétés étonnantescomme la superfocalisation ou la réfraction négative.Nous envisagerons également l’étude d’arrangements cristallins et verrons que lapériodicité induit des modifications sensibles dans le comportement du milieu tout enconstituant un levier de contrôle efficace.Enfin, la bulle est susceptible de se mouvoir et, par conséquent, de ressentir desforces de pression de radiation. En particulier, Nous verrons comment la force deBjerknes secondaire, issue du champ diffusé par une bulle vers l’une de ses voisines,peut être exploitée afin de manipuler une ou plusieurs bulles mobiles au voisinaged’une ou plusieurs bulles piégées. / A bubble undergoing an acoustic wave is likely to oscillate. The displacement of theair-fluid interface generates a local compression of the outer fluid where a scatteredwave is thus created. This very simple mechanism has been successfully described bythe famous Rayleigh-Plesset formula derived at the beginning of the previous century.At low frequencies, the resonant behavior (Minnaert) is responsible for a strongenhancement of the oscillations of the bubble which thus becomes a very efficientscatterer. In a realistic media, bubbles are not isolated. The interferences occurringbetween an infinity of scattering sequences make the description of the propagation alot harder to achieve.In this thesis, we introduce the effective theories that are classically adopted todescribe random bubbly liquids. After being compared to our numerical results, thesetheories are used in order to design bubbly materials featuring some interesting propertiessuch as superfocusing or negative refraction.The case of periodic assembly is addressed as well for both a simple square latticebubble raft and a cubic centered faces bi-periodic crystal. We show that the periodicityinduces an explicit modification in the dispersion of the medium and offers asimple tunable parameter.At last, we focus on the possibility for the bubble to move inside the host fluid andwhich is thus likely to experience an acoustic radiation pressure called Bjerknes force.We show how the secondary Bjerknes force, resulting from the wave scattered by abubble toward its neighbors, can be exploited in order to manipulate one or severalfree bubble flowing near one or several trapped bubbles.
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Exploring the Diversity of ExoplanetsSvensson, Rebecka January 2021 (has links)
The search for extrasolar planets had been ongoing for many years when Mayorand Queloz discovered 51 Pegasi b in 1995. It was a giant gas planet similar to Jupiter, but with a larger radius and of only half of Jupiter’s mass. Theso called Hot Jupiter was observed to orbit its host star 7 times closer thanMercury is orbiting the Sun. Theoretical models at the time stated that gasgiants could not form in such a short distance to the host star. Thus, thisdiscovery was completely unexpected. It was the beginning of a new field ofresearch where the diversity of exoplanets is the most remarkable discovery, challenging theoretical models. Thanks to the Kepler space telescope and anew generation of space missions such as TESS, thousands of exoplanets havebeen discovered and thousands of planet candidates await confirmation. In this thesis I have studied all confirmed exoplanets to this date, which havebeen discovered by the radial velocity and/or the transit method. The planetparameters and their stellar hosts are available on NASA’s Exoplanet Archive.For all planets < 100 M⊕, I have assessed and updated the parameters for eachplanet in particular when several solutions exist. There are several types ofplanets, but the focus of this work are small planets which come in two sizes: Rocky super-Earths, and the slightly larger and lower density sub-Neptune. Different types of planets have different radii and mass ranges, which togetherwith composition and interior structure are separating the types from each other. These mass and radii ranges are however not universally defined, and in thisreport the super-Earth and sub-Neptune ranges are discussed together with their typical characteristics. The radii and mass ranges of the two different classes of small planets are overlapping and are often difficult to classify. In particularfor planets in between 2 R⊕ and 3 R⊕, there is an ambiguity of structure and composition. This report will also investigate how planet properties depend on the stellarhost properties and on the orbital distances to the stars. One of my mainresults is that sub-Neptunes are common orbiting host stars with low metallicity, in contrast to super-Earths which are common orbiting host stars with highmetallicity. Other parameters, such as stellar effective temperature, seem to have no influence on planet properties. Super-Earth’s are found at a wide range of orbital distances while the sub-Neptunes cluster in a narrow range of orbital distances to their host star. Sub-Neptunes have an atmosphere, and are orbiting at distances where the atmosphere does not evaporate from intense host star radiation. If an atmospheree vaporates, only the rocky core of the planet is left. Thus, some super-Earths might have been sub-Neptunes that have lost their atmospheres. My second main result is that planets with characteristics of sub-Neptunes (with respect to density and interior structure) of 10 M⊕ to 15 M⊕ have radiibetween 2 R⊕ and 4.5 R⊕. Sub-Neptunes in the upper mass limit, between 15M⊕ to 17 M⊕, have radii from 2.6 R⊕ to 7.5 R⊕. And finally, my third result is the relation between planet density and equilibrium temperature. The density of all planets with masses < 15 M⊕ is Earth-like for equilibrium temperatures > 1400 K. For lower equilibrium temperatures corresponding to longer orbital periods, or lower-mass and cooler stars, planetswith masses < 15 M⊕ have a larger spread in densities. However, it never fallsbelow a diagonal linear trend in the density against equilibrium temperature diagram described by ρ = 2.6 × log10(Teq) − 7.46.
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FUZZY MARKOV RANDOM FIELDS FOR OPTICAL AND MICROWAVE REMOTE SENSING IMAGE ANALYSIS : SUPER RESOLUTION MAPPING (SRM) AND MULTISOURCE IMAGE CLASSIFICATION (MIC) / ファジーマルコフ確率場による光学およびマイクロ波リモートセンシング画像解析 : 超解像度マッピングと複数センサ画像分類Duminda Ranganath Welikanna 24 September 2014 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第18561号 / 工博第3922号 / 新制||工||1603(附属図書館) / 31461 / 京都大学大学院工学研究科社会基盤工学専攻 / (主査)教授 田村 正行, 准教授 須﨑 純一, 准教授 田中 賢治 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
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YOYO and POPO Dye Photophysics for Super-Resolution Optical NanoscopyPyle, Joseph R. 23 September 2019 (has links)
No description available.
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Att vara superanvändare och kontaktperson i Cosmic : En kartläggning av förväntan på och upplevelsen av att vara superanvändare och kontaktperson i Cosmic och hur kommunikationen till Sektion e-hälsa fungerar.Ogenvall, Camilla, Mitrovic, Melanie January 2023 (has links)
Sammanfattning Inledning: När journalsystemet Cosmic infördes i Region Jönköpings län (RJL) 2007 tillsattes superanvändare och så småningom även kontaktpersoner. Rollernas uppdrag var givna och arbetet rullade på. Nästan tjugo år senare är uppdragsbeskrivningarna samma trots att arbetet under årens lopp har förändrats. Sektion e-hälsa som är ansvarig för arbetet i Cosmic upplever en känsla av att arbetet inte fungerar optimalt och initierade ett förbättringsarbete. Men ett förbättringsarbete kan inte byggas på en känsla. Syfte: Syftet med denna studie är att kartlägga superanvändarnas och kontaktpersoners upplevelse av uppdraget, vilka förväntningar som finns på uppdragen och hur kontakten med Sektion e-hälsa fungerar. Metod: För att besvara syftets frågeställningar har en kvantitativ enkätundersökning med kvalitativa inslag använts. Genom intervjuer och fokusgrupper har fördjupande frågor kunnat ställas och deltagandet i Sektion e-hälsas möten och informationsträffar har gett en helhetssyn över förvaltningsorganisationen. Slutsats: Uppdragen som superanvändare och kontaktperson behövs för att säkerställa ett enhetligt arbetssätt inom RJL:s olika verksamhetsområden. Idag finns ingen etablerad struktur kring uppdragen vilket gör att rollernas ansvarsområden flyter ihop. Många upplever sina uppdrag som meningsfulla men känner samtidigt en stress över att inte hinna med dem. En allmän önskan är att förbättra kommunikationen till och samarbetet med Sektion e-hälsa. Den kompetens som finns ute i verksamheterna behöver bli sedd och tas med i förbättringsarbeten för Cosmic. / Abstract Introduction: When the journal system Cosmic was introduced in Region Jönköpings län (RJL) in 2007, super users and eventually also contact persons were appointed. The assignments of the roles were given, and the work continued. Almost twenty years later, the mission statements are the same even though the work has changed over the years. Sektion e-hälsa, which is responsible for the work in Cosmic, experiences a sense that the work is not working optimally and initiated an improvement work. But improvement work cannot be built on a feeling. Purpose: The purpose of this study is to map the superusers and contact persons experience of the assignment, what expectations there are on the assignments and how the contact with Sektion e-hälsa works. Method: To answer the questions of the purpose, a quantitative survey with qualitative elements has been used. Through interviews and focus groups, in-depth questions have been asked and participation in Sektion e-hälsas meetings and information meetings has provided a holistic view of the administrative organization. Conclusion: The assignments as superuser and contact person are needed to ensure a uniform way of working within RJL's various areas. Today, there is no established structure around the assignments, which means that the roles' responsibilities flow together. Many people experience their assignments as meaningful but at the same time feel a stress about not having time for them. A general desire is to improve communication to and cooperation with Sektion e-hälsa. The expertise that exists in the operations needs to be seen and included in improvement work for Cosmic. / <p>Examen i vårdadministration, YH-utbildning: 20 YH-poäng</p>
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THE APPLICATION OF SINGLE-POINT EDGE-EXCITATION SUB-DIFFRACTION MICROSCOPY FOR THE STUDY OF MACROMOLECULAR TRANSPORTTingey, Mark, 0000-0002-0365-5585 January 2023 (has links)
The development of super-resolution microscopy made it possible to surpass the diffraction limit of optical microscopy, enabling researchers to gain a nanometer scale understanding of cellular structures. While many applications have benefited from standard super-resolution microscopy, gaps remained making high-speed dynamic imaging in live cells impossible. To address this problem, single-point edge-excitation sub-diffraction (SPEED) microscopy was developed. This methodology enables the nanometer imaging of dynamic cell processes within live cells, the evaluation of subcellular structural information, the capacity to derive three-dimensional information from two-dimensional images within rotationally symmetric structures, and the interrogation of novel questions regarding the transport dynamics of macromolecules in a variety of cellular structures. Here, I have described the theory and method behind the current iteration of SPEED microscopy that we have developed and validated via Monte Carlo simulation. Further, a detailed description of how we have further developed SPEED microscopy to derive structural information within the nuclear pore complex as well as how SPEED has been applied to evaluate the export kinetics of mRNA. / Biology
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Aktuelle Herausforderungen der Kriminalistik: Qualifikationsarbeiten aus dem Studium der Polizei- und SicherheitsforschungBerthel, Ralph 21 June 2023 (has links)
Qualifikationsarbeiten im Bereich der Kriminalistik bewegen sich im Spannungsfeld von wissenschaftlichen Qualitätsansprüchen und (kriminal-)polizeilicher Praxisorientierung. Dass sich beides keinesfalls ausschließen muss, stellen die in diesem Band publizierten Masterarbeiten unter Beweis. Durchweg mit dem Prädikat „sehr gut“ bewertet, leisten sie beachtenswerte Beiträge zur Fortentwicklung der Kriminalistik als Wissenschaftsdisziplin sowie zu deren Theorie-Praxis-Transfer. Zugleich verdeutlichen sie die Vielfalt sowie die Komplexität der Herausforderungen, denen sich die Kriminalwissenschaften einerseits und die Sicherheitsakteure andererseits aktuell und künftig gegenübersehen. Konkret widmen sich die Arbeiten den folgenden Themen: •Der Gewalt auf der Spur – Schemabasierte Einbeziehung der Rechtsmedizin in das polizeiliche Ermittlungsverfahren bei Gewaltkriminalität gegen lebende Opfer •Wissenschaftliche Untersuchung humaner Exkremente zur Generierung einer effizienten Spurensicherungsmethode sowie Spurenauswertung •Einführung von „Super Recognizern“ in der Polizei Brandenburg – Eine Kosten-Nutzen-Analyse •Der Verdeckte Ermittler – Analyse kriminaltaktischer Anpassungserfordernisse
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