Dissertations / Theses on the topic 'White Light Interferometry (WLI)'
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Bora, Ethem. "Cylindrical Surface Analysis with White Light Interferometry." Thesis, Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE), 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-15308.
Full textSathiamoorthy, Karthick, and Tanjim Ahmed. "Construction and Validation of a White Light Interferometer." Thesis, Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE), 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-14378.
Full textGianto, Gianto. "Multi-dimensional Teager-Kaiser signal processing for improved characterization using white light interferometry." Thesis, Strasbourg, 2018. http://www.theses.fr/2018STRAD026/document.
Full textThe use of white light interference fringes as an optical probe in microscopy is of growing importance in materials characterization, surface metrology and medical imaging. Coherence Scanning Interferometry (CSI, also known as White Light Scanning Interferometry, WSLI) is well known for surface roughness and topology measurement [1]. Full-Field Optical Coherence Tomography (FF-OCT) is the version used for the tomographic analysis of complex transparent layers. Both techniques generally make use of some sort of fringe scanning along the optical axis and the acquisition of a stack of xyz images. Image processing is then used to identify the fringe envelopes along z at each pixel in order to measure the positions of either a single surface or of multiple scattering objects within a layer.In CSI, the measurement of surface shape generally requires peak or phase extraction of the mono dimensional fringe signal. Most of the methods are based on an AM-FM signal model, which represents the variation in light intensity measured along the optical axis of an interference microscope [2]. We have demonstrated earlier [3, 4] the ability of 2D approaches to compete with some classical methods used in the field of interferometry, in terms of robustness and computing time. In addition, whereas most methods only take into account the 1D data, it would seem advantageous to take into account the spatial neighborhood using multidimensional approaches (2D, 3D, 4D), including the time parameter in order to improve the measurements.The purpose of this PhD project is to develop new n-D approaches that are suitable for improved characterization of more complex surfaces and transparent layers. In addition, we will enrich the field of study by means of heterogeneous image processing from multiple sensor sources (heterogeneous data fusion). Applications considered will be in the fields of materials metrology, biomaterials and medical imaging
Oliveira, Rafael Figueiredo de. "Evaluation of Proposed Natural Corrosion Inhibitors for X-52 Carbon Steel in Ethanol Media." University of Akron / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=akron1448385629.
Full textHissmann, Michael. "Bayesian estimation for white light interferometry." Berlin Pro Business, 2005. http://shop.pro-business.com/product_info.php?products_id=357.
Full textFerri, Carlo. "White light interferometry in measurements of micro volumes." Thesis, Cardiff University, 2006. http://orca.cf.ac.uk/54574/.
Full textBhatia, Vikram. "Signal processing techniques for optical fiber sensors using white light interferometry." Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-09192009-040440/.
Full textYu, Bing. "Development of Tunable Optical Filters for Interrogation of White-Light Interferometric Sensors." Diss., Virginia Tech, 2005. http://hdl.handle.net/10919/27496.
Full textPh. D.
Li, Beinan. "Optical audio reproduction for stereo phonograph records by using white-light interferometry and image processing." Thesis, McGill University, 2011. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=103586.
Full textCette thèse présente une nouvelle approche de reproduction optique d'enregistrements phonographiques stéréo. L'enregistrement phonographique s'est imposé, vers la fin du XIXème siècle, comme la technologie d'enregistrement de référence partout dans le monde. Il existe donc une pléthore de cylindres et autres disques où ont été gravés discours, morceaux de musique, et autres artefacts culturel sonores. La préservation de ces enregistrements sonores phonographiques est donc une préoccupation mondiale. Le présent travail de recherche propose une approche alternative de numérisation des enregistrements phonographiques stéréo en vue de leur éventuelle préservation. En effet, à partir de l'acquisition optique du profil (en trois dimensions) de la surface d'enregistrement du disque, les signaux audio peuvent être reconstruits grâce à nos algorithmes d'analyse d'images. Cette thèse examine les étapes de la reproduction optique audio stéréo à partir d'enregistrements phonographiques sur disques stéréo en utilisant l'interférométrie en lumière blanche. Ces étapes comportent: l'acquisition du profil de la surface d'enregistrement d'un disque 3D en utilisant un microscope commercial interférométrique en lumière blanche ; l'extraction des ondulations du sillon, qui encode l'information audio stéréo en utilisant nos algorithmes de traitement d'images ; et finalement, la reproduction du signal audio stéréo depuis les ondulations du sillon par des techniques de traitement du signal. Le processus complet est évalué sur un enregistrement stéréo test comprenant des signaux sinusoïdaux et un enregistrement musical. La qualité de l'audio reproduit par voie optique est évaluée de façon quantitative et comparée avec celle de l'audio numérisé de manière « traditionnelle », à l'aide d'une platine. Cette thèse s'articule en trois parties. La première comporte une introduction des principes nécessaires à la reproduction d'enregistrements phonographiques stéréo par voie optique. Plus précisément, les principes de la technologie d'enregistrement phonographique sont passés en revue ; l'état de l'art des efforts de reproduction optique des enregistrements phonographiques sur disques et cylindres est présenté ; et enfin, les techniques optiques pertinentes incluant l'interférométrie en lumière blanche sont décrites. La deuxième partie livre une présentation détaillée du processus de reproduction optique que nous avons développé. Dans la troisième partie, l'évaluation quantitative de la qualité de la restitution du signal audio obtenue par notre procédé est aussi décrite. La thèse se conclue sur un bilan des défis et des directions possibles dans le futur développement de notre approche de reproduction des signaux audio par voie optique.
Wylde, Clarissa Eileen Kenney, and Clarissa Eileen Kenney Wylde. "The Art of Optical Aberrations." Thesis, The University of Arizona, 2017. http://hdl.handle.net/10150/624090.
Full textRomare, Dario. "The application of adaptive linear and non-linear filters to fringe order identification in white-light interferometry systems." Thesis, City, University of London, 1998. http://openaccess.city.ac.uk/19993/.
Full textOlszak, Artur G., and Chase Salsbury. "Spectrally controlled interferometry for measurements of flat and spherical optics." SPIE-INT SOC OPTICAL ENGINEERING, 2017. http://hdl.handle.net/10150/627191.
Full textOtto, Marc-André [Verfasser], and Otmar [Gutachter] Loffeld. "Automated high-precision crack detection in airplane combustion chamber liners using white light interferometry / Marc-André Otto ; Gutachter: Otmar Loffeld." Siegen : Universitätsbibliothek der Universität Siegen, 2020. http://d-nb.info/122862707X/34.
Full textHan, Ming. "Theoretical and Experimental Study of Low-Finesse Extrinsic Fabry-Perot Interferometric Fiber Optic Sensors." Diss., Virginia Tech, 2006. http://hdl.handle.net/10919/27825.
Full textPh. D.
Ivanov, Georgi Pavlov. "Fabry-Perot Sapphire Temperature Sensor for Use in Coal Gasification." Thesis, Virginia Tech, 2011. http://hdl.handle.net/10919/32931.
Full textMaster of Science
Ma, Cheng. "Modeling and Signal Processing of Low-Finesse Fabry-Perot Interferometric Fiber Optic Sensors." Diss., Virginia Tech, 2012. http://hdl.handle.net/10919/77225.
Full textPh. D.
Zhu, Yizheng. "Miniature Fiber-Optic Sensors for High-Temperature Harsh Environments." Diss., Virginia Tech, 2007. http://hdl.handle.net/10919/27762.
Full textPh. D.
Zhao, Xin. "Study of Multimode Extrinsic Fabry-Perot Interferometric Fiber Optic Sensor on Biosensing." Thesis, Virginia Tech, 2006. http://hdl.handle.net/10919/34534.
Full text
In this thesis, a multimode fiber-optic sensor has been developed based on extrinsic Fabry-Perot interferometry (EFPI) for the measurement of optical thickness in self-assembled thin film layers as well as for the immunosensing test. The sensor was fabricated by connecting a multimode fiber (MMF) and a silica wafer. A Fabry-Perot cavity was formed by the reflections from the two interfaces of the wafer. The negatively charged silica wafer could be used as the substrate for the thin film immobilization scheme. The sensor is incorporated into the white-light interferometric system. By monitoring the optical cavity length increment, the self-assembled thin film thickness was measured; the immunoreaction between immunoglobulin G (IgG) and anti-IgG was investigated.
Master of Science
Al-Mamun, Mohammad Shah. "Development of a Miniature, Fiber-optic Temperature Compensated Pressure Sensor." Thesis, Virginia Tech, 2014. http://hdl.handle.net/10919/71308.
Full textMaster of Science
Blecha, Martin. "Pracoviště pro optickou interferometrii." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2008. http://www.nusl.cz/ntk/nusl-217262.
Full textKlempner, Adam R. "Development of a modular interferometric microscopy system for characterization of MEMS." Link to electronic thesis, 2007. http://www.wpi.edu/Pubs/ETD/Available/etd-010407-173332/.
Full textKeywords: vacuum; shape and deformation measurement; MEMS; vibrometry; scanning white light; Interferometry; thermal; vibration. Includes bibliographical references (136-139 leaves ).
Ås, Sigmund. "Fatigue Life Prediction of an Aluminium Alloy Automotive Component Using Finite Element Analysis of Surface Topography." Doctoral thesis, Norwegian University of Science and Technology, Faculty of Engineering Science and Technology, 2006. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-758.
Full textA 6082 aluminium alloy has been characterized with regard to the influence of surface roughness on fatigue strength.
Fatigue life testing of smooth specimens was used to establish reference curves for the material in extruded and forged T6 condition. The extruded material was found to have better fatigue strength than the forged material, although the cyclic stress-strain response was similar for both. The forged material was tested in T5, T6 and T7 tempers, showing no significant difference in fatigue strength.
Surface roughness was created by circumferential grinding of cylindrical test specimens, and the surface topography was measured using a white light interferometry microscope. The measurements proved to be accurate, although errors were observed for certain surface features. Residual stresses were quantified by X-ray diffraction. Compressive residual stresses of around 150 MPa were found in both rough and smooth specimens. Load cycling did not significantly alter the surface residual stresses.
Stress solutions ahead of all major surface grooves were found using a linear elastic material model. Estimates of cyclic stresses and strains were calculated in the notch roots using different Neuber corrections of the linear solution. The results were compared to finite element analysis employing a bilinear kinematic hardening model. A generalized version of the Neuber correction was found to be within 20% of the nonlinear finite element results.
Several empirical models for the notch sensitivity factor were investigated. These were found to be unable to describe the notch influence on fatigue life and initiation life. In order to follow this approach, it was recommended that different test specimens should be used where the short fatigue crack growth could be monitored.
It was shown that microstructural fracture mechanics theories could be used to estimate the fatigue limit of rough surfaces. In some cases, initiation from material defects or weaknesses would override the influence of surface geometry. In one specimen, the initiation appeared to have started as at a de-bonded grain, while in other cases, initiation was thought to have started at larger second phase particles embedded in notch roots. Further work in this area should focus on statistical descriptions of surface roughness, inherent material defects, and their interaction.
Silva, Luiz Pinheiro Cordovil da. "Transformador óptico por interferometria de luz branca para medição de altas tensões." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/3/3143/tde-17042006-105554/.
Full textA new approach to perform measurement of potentials in high voltage levels using electrooptical Pockels sensors is presented here. This work describes an application of the White Light Interferometry technique to a high voltage optical fiber measurement system. In this system the information is encoded in the spectrum of the light, allowing the measurement to be independent of the optical power transmitted by the optical fiber link. A prototype was built and tested under excitation of a.c. voltages up to 20 kV in 60 Hz showing good response and demonstrating the feasibility of this method.
Silva, Luiz Pinheiro Cordovil da. "Interferômetros recuperadores de baixa tensão de meia onda para sistemas interferométricos de luz branca utilizando moduladores eletro-ópticos." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/3/3143/tde-08122011-153421/.
Full textThis work has as objective the study and development of low half-wave voltage recovery interferometers using electro-optical modulators to be applied to white light interferometric systems. This work is a continuation in the research carried out by the author to obtain his master degree, in which it was developed and tested an electro- optic sensing system capable to measure direct voltage to 69.4 kVrms. In the present work the optical signals processing system is improved by developing a new recovery interferometer based on integrated optics. To develop the proposed subject, initially a review of the literature, based on books, articles and thesis, has been done aiming to identify the State of the Art related to electro-optic modulators and helping to define the most suitable type of modulator for the desired application. The study resulted in the selection of an integrated optical device arranged in an unpublished configuration that was applied to a prototype of optical voltage transformer, intended to measure high voltage levels. The performance of this prototype was compared with a previous version. The results of this work increase the knowledge of the construction techniques of recovery interferometers based on integrated optic devices applicable to the recovering of optical signals in interferometric systems for high voltage measurement.
Huang, Chao-Nan, and 黃兆男. "Stress measurement with white light interferometry." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/32235889126077202596.
Full text明新科技大學
電子工程研究所
97
Currently there is a need for optical interference filters coated on plastic and flexible substrates in high technology industry. Since Young’s modulus and thermal expansion coefficients of plastic and flexible substrates are quite different from the glass, the stress of coated films on plastic and flexible substrates is more complicate. We build a white-light vertical scanning Michelson interferometer to measure stress of optical thin films. The white-light interferometer is based on short white-light coherence length and measure surface profiles of plastic and flexible substrates by a vertical scanning method with zero-order interference fringe identification. Stress of thin films will be calculated by comparing the deflection of the substrates before and after film deposition. Besides, the relationship between applied voltages and displacement of piezoelectric transducer devices was also accurately measured by both using analyses of phase shifting interferometry algorithms and setting up a Twyman-Green interferometer.
Chang, Chia-Yuan, and 張家源. "White Light Phase Shifting Interferometry for Surface Profilometry." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/72572170054195677152.
Full textLing, Wei-Cheng, and 凌維成. "Surface Profilometry of Micro Device with White Light Interferometry." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/06364741933686812854.
Full text國立中興大學
機械工程學系
93
This research uses white light illumination and two identical microscope objectives to build a Linnik interferometer and also use a objective which specially made for interferometer to build a Mirau interferometer., The surface profile of the sample can be reconstructed by phase shift interferometry, phase unwrap or zero order interference fringe identification. Because the usage of microscope objective, the measurement area and the height resolution are suitable for measuring micro devices. In this research, a flat mirror, standard sphere and a step height have been measured. The phase shift interferometry successfully measured samples that under the height difference limit ( ), between two adjacent pixels, and the step height can be measured correctly by zero order interference fringe identification. During the experiment, we found a phase shift which is not controlled by the interferometer has a long term influence of all our measurements. We found this phase shift correlates with the temperature. The phase shift caused by temperature will introduce measurement error and degrade the repeatability of the interferometer.
Yeh, Yi-Lin, and 葉易霖. "Research on the Vertical Scanning of White-Light Interferometry." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/27921651596661531187.
Full text國立臺灣大學
機械工程學研究所
92
This study aims to establish the 3D profile measurement techniques of white-light interferometry with large vertical and horizontal measuring ranges. The purpose includes a complete investigation of the SIS-1000 (SNU Precision Company) surface profilometer for its operation principles and component specifications. The core of the research is to develop an effective methodology for large-range and long-depth 3D profile measurement with nano-scale resolution and accuracy. The measuring method includes vertical scanning and image merging method (Geomagic Studio) by using SIOS laser interferometer for the purpose of precision positioning. The proposed “enhanced vertical scanning method” combines traditional vertical scanning with image merging method. Along with the outcome of experiments, this achieves the perfect ability for 3D reconstruction techniques.
Hißmann, Michael [Verfasser]. "Bayesian estimation for white light interferometry / presented by Michael Hißmann." 2005. http://d-nb.info/976058693/34.
Full textHong, Wen-Ming, and 洪文明. "White-light Phase Shifting Interferometry for Three Dimension Surface Measurement." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/93134633335835686657.
Full text國立交通大學
光電工程所
91
In order to study the application of white-light phase-shifting interferometry (PSI) in three dimension surface measurement ,we use traditional PZT phase shifting and achromatic phase shifting .We compare and discuss the results from both the phase-shifting methods. The measurement system is a Linnik interferometer. The light source is a halogen lamp,which is a polychromatic light source,covering the visible spectral range . In the theory we assume that the polychromatic light source has a Gaussian power spectral density, so we use a narrow bandwidth filter with central wavelength 629.5nm and broad bandwidth filter with central wavelength 550nm, to satisfy the theoretical requirement. To verify our measurement results,we compare the surface profiles measured by our interferometer with that by Zygo instrument. By using phase shifting, we can achieve high vertical resolution, but have a limited vertical depth. If we consider the characteristics of the short coherence length of white-light and make a vertical scanning to find the location of maximum intensity, we can greatly improve the measurement of vertical range.
SHEN, Ming-Sing, and 沈明興. "Design and Fabrication of Auto-Focusing Michelson White Light Interferometry." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/48447862422042706875.
Full text國立成功大學
機械工程學系碩博士班
95
The white light interferometer which has characteristics of non-destruction and nanometer precision in vertical resolution is helpful for the development of precise nanometer measurement. This paper use Michelson white light interferometry and the technique of Auto-Focusing to develop a system of three dimensional surface measurement for Auto-focusing Michelson white light interferometry . In order to set up the three-dimensional profile of the sample, we search the range of interference by auto-focusing first, then search the position of highest intensity of light by analyzing interference fringe .In the Auto-Focusing method, we adopt passive auto-focusing. Passive auto-focusing has two important parts: sharpness measures, and rule search algorithms. In the analysis of interference fringes, we introduce Fourier Transform method, Peak detection, and phase-shifting in this paper. In the collocation of Michelson interferometer and the auto-focusing method, we use the corrected Rule-based algorithm to make PZT to scan the whole field interference fringes to obtain the three-dimensional profile. In the analysis of interference fringes, we found that the phase-shifting method has better accuracy and stability with different magnification. And we also found that with low different magnification, the limits of measurement is affected by the horizontal resolution.
劉韋良. "Measuring Stress of Thin Films with Stitch of White-light Interferometry." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/97681934960482818006.
Full text明新科技大學
電子工程研究所
98
The stress in thin films is well known to be very important in all optical coating applications, because film stress produces several undesirable phenomena, such as the cracking or peeling of the film and the bending of the substrate. In this study, stress is measured by a white-light Michelson interferometer, which is based on short white-light coherence length and measures surface profiles of substrates by a vertical scanning method with zero-order interference fringe identification. We used the stitch technology to expand the measurement area of the substrates with addition of tilt terms of X and Y axes when the stress was measured by using the white-light Michelson interferometer. By using the Zernike polynomials fitting for the wavefront being tested, surface contours for the uncoated and coated substrates are obtained. Stress is calculated by comparing the deflection of the substrates before and after film deposition. The results show the white-light Michelson interferometer with stitch technology is capable of measuring large scope on the substrates.
Lin, Yi-Hsuan, and 林宜萱. "Innovative 3-D Surface Profilometer Using White Light Lateral Scanning Interferometry." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/6675nt.
Full text國立臺北科技大學
機電整合研究所
97
An in-situ 3-D surface profilometer for reconstructing micro surface profiles with a long depth measuring range and a nano-scale resolution was developed using innovative white light lateral scanning interferometry (LSI). Current measuring field of view (FOV) of conventional white light interferometers is currently limited by microscopic views of the existing interferometric objectives, such as Michelson, Mirau or Linnik design. Moreover, vertical scanning operation required for acquiring volumetric interferometric data is extremerely time consuming and makes white light vertical scanning interferometry (VSI) infeasible for in-situ automatic optical inspection (AOI) on micro 3-D structures. The traditional LSI methods were mainly developed by tilting the whole optical axis with respect to the scanning direction of a sample’s surface underlying inspection, in which it has one inherent difficulty in effective collision avoidance between the optical objective and the object’s surface. To resolve this, a new white light LSI method was developed here by controlling the tilting angle of the reference mirror in the interferometric objective. With the proposed optical configuration, the surface is inspected at a tilting angle with respect to the maximum coherence plane of the interferometric system along its lateral scanning direction when the objective lies perpendicularly with the tested surface. In addition, a calibration method was developed to establish an accurate mathematical mapping model between the object depth and the lateral axis. To evaluate the feasibility of the methodology, a calibrated step height was measured for evaluating the accuracy and repeatability. Some industrial samples, such as photon spacers and other microstructures fabricated by -nano imprinting processes, were measured to verify the actual performance on real components. It was found that the measurement repeatability was controlled less than 60 nm within one standard deviation for a maximum measurable depth of 27.21 μm.
Chen, Chien-Cheng, and 陳建丞. "White-light Achromatic Phase Shifting Interferometry for Three Dimension Surface Profile Measurement." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/12748259146553563444.
Full text國立交通大學
光電工程系所
92
This work focuses on the abilities of white-light phase-shifting interferometry (WLPSI) in 3-D surface profile measurement. We set up a Linnik type interferometric microscope in which an achromatic phase-shifting method with rotating waveplate is used. A quartz tungsten-halogen(QTH) lamp, covering the visible spectral range 400~700 nm, is used as the white-light source. In this theory the light source is required to have a Gaussian spectral power distribution. However, the QTH lamp does not have a good Gaussian spectral distribution. Two narrowband band-pass filters with central wavelength at 589.5nm and 629.5nm are used in order to get better Gaussian distribution. The measured results are compared with those measured by a Zygo instrument(Newview5000). In this work, the phase-shifting module is placed at input and output ends for comparison. The comparison shows that the input end case has better performance than the output end case in the measurement accuracy, contrast and repeatability. In the input end case the shift of interference pattern at the image plane can be avoided when the waveplate rotates in the phase-shifting module. Although phase-shifting method usually gives very good vertical resolution, it still suffers from a limited measurement range in the vertical direction. If we consider the characteristics of the short coherence length of white-light, this method combined with a vertical scanning of maximum intensity position can increase the vertical depth measurement range greatly.
Wang, Huai-Yi, and 王懷逸. "Application of White-light Scanning Interferometry on Localized Surface Plasmon Resonance Sensor." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/75478268426276217461.
Full text國立中央大學
光電科學與工程學系
105
This article aims to set up a biosensor based on white-light scanning interferometry (WLSI) and applies to localized surface plasmon resonance (LSPR) sensor. In the WLSI system, the amplitude changes, as functions of wavelength, is retrieved by means of Fourier transform of the correlograms (interferograms in vertical direction). The Fourier amplitude method is capable to measure environmental changes in refractive index which results in a red shift of the amplitude (or spectrum) of gold nanoparticles (GNPs) solution. Meanwhile, the article shows that the performance of a spectrometer with poor spectral resolution is improved by the spectral centroid algorithm significantly because more data points (wavelengths) are considered for signal-to-noise ratio improvement Additionally, the sources of errors in the WLSI system, inclusive of the accuracy of wave-number and illumination non-uniformity, are improved. We use the spectrum of an edge filter as a check of the wavenumber accuracy. The result shows the best match with frame interval of 71 nm. In comparison to a spectrometer, the average spectrum error is 1.04 %. The illumination uniformity is also improved from 41.34 % to 92.49 % by the program correction. A method to measure the refractive index variation in the WLSI system is described in the article. The limit of detection (LOD) is 1.2"×" 10-3 RIU (Refractive Index Unit). The bio-applicability was investigated using the rs242557 tau gene, an Alzheimer's and Parkinson’s disease biomarker. The LOD was calculated as 15 pM.
Yeh, Li-chi, and 葉力旗. "Stitching of White-Light Interferometry Profile by Applying Digital-Image-Correlation Method." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/46532213493711784816.
Full text國立成功大學
機械工程學系碩博士班
95
This thesis aims to build a large horizontal range of white light interferometry techniques applied in the mirco-structure surface profile measurement. It particularly focuses on the surface profile of micro-eletro-mechanical to perform the non-destructiveness and high resolution profile measurement. Based on its frequency spectrum characteristics of continuous wavelength, the white light interferometry technique shortens coherence length significantly. In experiment setup, we adopt a Mirau objective which specifically designed for interferometer to build the white light interferometer, and work with phase shifting algorithm to find out the position of the maximum intensity of interference fringes and finally reconstruct the topography of sample. In addition, we compare the result of experiment with the Alpha-Step instruments, and evaluate 3 sigma of measurement system. As for the large horizontal measurement range, we stitch the image and 3D profile of different position by using digital-image-correlation method. Firstly, we capture the two images that have the same feature from different position to transact the Laplacian filter, and select the area to compare each other to find out the stitching position from overlapping area of the two images. Finally, this study applies image stitching position to stitch the 3D profile of the white light interferometry and confirm the research feasibility. The experiment results show that stitching precision will achieve 1 pixel when standard deviation of comparison area of image exceed 7.1,and the error of 3D profile stitching is under 20 nm.
陳政儒. "Refractive Index and Thickness of Thin Films Measured by White Light Interferometry." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/30244495543722605760.
Full text明新科技大學
電子工程研究所
99
A white-light vertical scanning Michelson interferometer has been successfully built to measure refractive index and thickness of optical thin films in the study. The white-light interferometer is based on short white-light coherence length and measure optical paths between both top and bottom faces of thin films by a vertical scanning method with zero-order interference fringe identification. Refractive index and thickness of thin films are determined by fitting interference patterns of white-light intensity with numerical analyses. The method of measuring refractive index and thickness of optical thin films has the advantages of inherently high sensitivity and accuracy.
Lien, Chun-Tai, and 連俊泰. "Innovative Anti-vibration Technique for On-line White-light Vertical Scanning Interferometry (VSI)." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/3q3u7b.
Full text國立臺北科技大學
自動化科技研究所
97
White light interferometer (WLI) has become a popular method for measuring micro surface profiles having a large height range with a nano-scale resolution. However, it is easily influenced by environmental vibration or noisy disturbances, which significantly restricts its usefulness and application for in-field inspection. Tremendous research effort has been invested to overcome the vibration-induced measurement problems. Thus, in this research, a novel white-light optical interferometric system was developed to minimize measurement errors potentially caused by environmental vibrations. The novel developed systemTM is composed of a white-light LED light source, a narrow bandpass filter, a Mirau objective, a PZT for vertical scanning and two image sensing devices. Using the development, the vibration displacement can be accurately monitored and compensated for accurate vertical scanning interferometry (VSI). From the preliminary experimental results, it is verified that nano-scale displacement detection for a vibration having a bandwidth of 20 Hz can be effectively achieved. The feasibility of the anti-vibration white-light VSI is further verified by performing an industrial in-field test.
Bold, Geoffrey Terence. "White Light Feedback Interferometry for Aberration Correction, and Near-Real-Time Phase-Difference Amplification." 2002. http://hdl.handle.net/2292/855.
Full textDu, Jen-Wu, and 杜振武. "Refractive Index、Extinction Coefficient and Thickness of Thin Films Measured by White Light Interferometry." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/jxn48u.
Full text明新科技大學
電子工程研究所
101
In this study, a white-light vertical scanning Michelson interferometer has been successfully built to measure refractive index, extinction coefficient, and thickness of optical thin films. The white-light interferometer, based on short white-light coherence length, measures the optical path between the top and bottom faces of a thin film by a vertical scanning method with zero-order interference fringe identification. Refractive index, extinction coefficient, and thickness of thin films are determined by fitting interference patterns of white-light intensity using a LabVIEW program with a simplex algorithm, made by ourselves. The differences of refractive index, extinction coefficient, and thickness of a dielectric film between measurements of the white-light interferometer and an ellipsometer are within 0.1, 0.01, and 5nm over the 400-700nm wavelength range. The differences of refractive index, extinction coefficient, and thickness of a thin metal film between measurements of the white-light interferometer and an ellipsometer are within 0.4, 0.2, and 1nm over the 400-700nm wavelength range. The method of measuring refractive index, extinction coefficient, and thickness of optical thin films has the advantages of inherently high sensitivity and accuracy.
Wang, Pei-Syuan, and 王珮璇. "A New Approach to Calculate the Profile Measurement using White-Light Interferometry with Uneven Sampling Spacing." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/82d39q.
Full text國立臺北科技大學
機電整合研究所
101
The white-light interferometry has been broadly used in micro/nano-structure in recent years. As environmental vibration affects the measurement accuracy, it is necessary to modulate offset-compensation of vibration. There are two methods for compensating the displacement of vibration. The first method is to use the PZT as feedback. The other method is to detect the displacement and use the appropriate algorithm to attenuate and correct adjustments. Of the two methods, the former relies on the accuracy of PZT. Its limitation is that the bandwidth of PZT stays low, causing delay to the compensatory system. The aim of this study is to use the embedded system in hope of achieving high-coherence by effectively mastering white-light interference fringe to calculate the offset with phase-shift algorithm. It focuses on signal processing with high-coherence interference fringe, which can be sampled in high and accurate resolution. According to the white-light interference principle, the highest peak of white-light interference fringe is the height of the object. Hence, it can be used as a method to estimate the peak using mathematical algorithm. White-light interferometry measurement assumes equidistant sampling condition, but the measurement is in aperiodic waveforms. This study estimated the peak of fringe which is sampled in unequal, aperiodic and asymmetric. In order to obtain the peak position of the white-light interference, the study uses white-light curve fitting algorithm for fitting sampling points, which can be applied to unequal, asymmetric signals. By using the algorithm to estimate the peak point of the white-light interference fringe, this study reconstructs the three dimension outlines of components to be analyzed. The algorithm developed by this study can calculate with the standard deviation of 2.22 nm, which is one of the better algorithms so far.
Jen, Shu-yi, and 任書毅. "3-Dimensional Static and Dynamic Measurements by a White-Light Achromatic Phase-Shifting Interferometry on Microscope." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/32285247624249746459.
Full text國立成功大學
機械工程學系碩博士班
95
A 3-Dimensional profilometer focuses on the measurement of microstructure surface profiles by using a new white-light phase-shifting interferometry was developed. This system originates from interferometric microscope with Mirau object lens. This kind of upright microscope differs from other interferometries, such as Linnik, Michelson, Fizeau interferometry, which were installed on optical table. The upright microscope can measure an item not only static but also kinematic specimen. Unlike the general kinematic microscopes, the setup uses a polarizer phase-shifter without using a PZT for a Mirau object lens. We combine Linnik interferometry on an upright microscope, and co-operate with a polarizer phase-shifter. The measurement with sub-wavelength scale resolution is achieved by measuring the fringe contrast function of the white-light interferogram. This non-destructive, non-contact optical interferometry can offer desirable depth measurement sensitivity and density of lateral resolution. This system is based on an available phase-shifters which employ a rotating polarization component at the light source end of the interferometry. In this new setup, a half-wave plate and a quarter-wave plate were used to modulate the phase difference of incident beams before entering microscope. The demanding precision of a polarization phase-shifter is not as high as the requirement in a traditional phase-shifting method with PZT for a Mirau object lens. Therefore, by using the technique, the speed of image processing will be faster than the speed of traditional phase-shifting method by PZT for a Mirau object lens. This new method has no problem like the noises caused by a PZT from the traditional one.
Liao, Hsin-Hung, and 廖信宏. "A Micromirror Module using a MEMS Digital-to-Analog Converter and its Application for White-Light Interferometry System." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/67992207090398620449.
Full text國立臺灣大學
機械工程學研究所
99
In this work, we develop a microelectromechanical digital-to-analog converter mirror module (M-DACMM), and demonstrate its application for non-contact optical surface profiling systems. The proposed device generates nano-scale step motions that are proportional to input digital signals. The M-DACMM device, which consists of a large-area mirror, a digital-to-analog converter and 8 electrostatic parallel-plate actuators, can be monolithically fabricated by using a proposed micromachining process. Also, the process is suitable for releasing a large-area mirror (1mm in diameter) without the need of etching holes on the mirror surface. The transient responses of the mirror module are also measured and discussed. The switching time between two input binary states is less than 80 ms. The measured full-scale displacement is 1050 nm, and the motion step is 72 nm. The M-DACMM device has advantages of high position accuracy, high repeatability, and small size. Also, the device can be easily controlled by a simple actuation circuit. The M-DACMM is successfully installed on a white-light interferometry system as a reference mirror module. The surface-profiling results measured by the system are also presented.