20.500.12556/RUL-128157 Numerična analiza meritev difuzne refleksije z uporabo integracijske krogle z notranjim izvorom svetlobe Numerical analysis of diffuse reflectance measurements using an integrating sphere with an internal light source Meritve spektrov difuzne reflektivnosti z uporabo integracijske krogle so pogosto uporabljen eksperimentalni pristop za karakterizacijo optično sipajočih snovi in struktur, na primer bioloških tkiv in organov. Analiza tako dobljenih spektrov praviloma temelji na prilagajanju analitičnih ali numeričnih napovedi v definicijski geometriji, kjer vzorec obsevamo z ozkim svetlobnim snopom in zajamemo povratno sipano svetlobo iz dovolj velike okolice. A komercialni instrumenti pogosto delujejo obratno: Vzorec obsevajo izotropno in zajamejo svetlobo, ki izhaja iz sredine obsevane ploskve v razmeroma majhen prostorski kot. Smiselnost take meritve temelji na veljavnosti predpostavke o simetriji na obrat časa. V okviru magistrske naloge preverimo, ali pride do kršitve te predpostavke, analiziramo nastalo napako in preverimo možnost za njeno odpravo pri analizi opisanih meritev. To dosežemo z uporabo natančne numerične simulacije razmer v eksperimentu, ki temelji na metodi Monte Carlo. Measurements of diffuse reflectance spectra using an integrating sphere are commonly used to characterize optically scattering materials and structures, such as biological tissues and organs. The analysis of the thus obtained spectra is generally based on the adjustment of analytical or numerical predictions in definition geometry, in which the sample is irradiated with a narrow light beam and the diffusely reflected light is captured from a large enough surrounding area. However, many commercial instruments work the other way around: The sample is isotropically irradiated and the light emanating from the center of the irradiated area into a relatively small solid angle is analyzed. The validity of such measurement is based on the validity of the assumption of time reversal symmetry. In this master's thesis, we check whether this assumption is violated, analyze the error and check the possibility of its elimination when analyzing the described measurements. This is achieved by using a detailed numerical simulation, which is based on Monte Carlo method and with which we replicate the experimental procedure. Difuzno refleksijska spektroskopija transport svetlobe v sipajočih snoveh integracijska krogla metoda Monte Carlo beli standard človeška koža Diffuse reflectance spectroscopy light transport in scattering materials integrating sphere Monte Carlo method white standard human skin true false false Slovenski jezik Angleški jezik Magistrsko delo/naloga 2021-07-04 08:15:09 2021-07-04 08:15:13 2024-05-29 14:12:04 0000-00-00 00:00:00 2021 0 0 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 118135 69086467 2698.pdf 2698.pdf 1 B54116405CB0F40788066D05E0737739 4904baa14579fd323526f0223373924ad5496da2fce3862f6ab3dcd9ca9cd416 122a2e12-dc8f-11eb-a523-00155dcfd717 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=144795 Fakulteta za matematiko in fiziko 0 0 0