Fundamentals of a metal surface imaging system based on laser-optic principles

Bektaş, Murat
The confocal laser-scanning microscope (CLSM), known simply as a confocal microscope, is an important instrument which allows us to observe an object or a surface in three-dimensions with confocal microcopy technique. The basic difference of confocal microscopy is detecting the in- focused light, while the out of focus light is blocked out by the help of a pinhole. By this optical dissection ability of confocal microcopy, CLSM provides the images of investigated object or the surface with higher resolution and contrast as against conventional microscopic systems. Various types of Laser Scanning confocal microscopes have been developed and due to its high resolution and contrast they have become an invaluable tool for investigations in many areas like biology and medicine. In addition to its wide range of use, confocal microscope can be used for detecting of possible defects on metal surfaces. In this thesis our goal was to develop the analytical and theoretical back ground necessary for the successful completion of a laser/optic system coupled to a fiber bundle waveguide based on confocal scanning principles to effectively image a non-uniform, metal surface with speed and precision in order to assess any surface damage. In addition to this analysis we demonstrate a working confocal microscopy set-up and investigate the factors which affect the image quality by the experiments conducted in METU (Middle East Technical University) Laser Laboratory.


Development of compact terahertz time-domain terahertz spectrometer using electro-optic detection method
Metbulut, Mukaddes Meliz; Altan, Hakan; Department of Physics (2009)
The goal of this thesis is to describe development of compact terahertz time-domain spectrometer driven by a mode-locked Ti:Sapphire laser. The terahertz radiation was generated by photoconductive antenna method and detected by electro-optic detection method. In this thesis, several terahertz generation and detection method, working principle of terahertz time-domain spectroscopy and its applications are discussed. We mainly focused on working principle of terahertz time-domain spectroscopy and characteriza...
Design of reflective and antireflective coatings for space applications
Eroğlu, Hüseyin Cüneyt; Esendemir, Akif; Department of Physics (2009)
In order to improve the efficiency of various optical surfaces, optical coatings are used. Optical coating is a process of depositing a thin layer of a material on an optical component such as mirror or lens to change reflectance or transmittance. There are two main types of coatings namely; reflective and antireflective (AR) Coatings. Reflective and antireflective coatings have long been developed for a variety of applications in all aspects of use; for optical and electro-optical systems in telecommunicat...
Development of a compact time-domain terahertz spectrometer using photoconductive antenna detection method
Güngör Erözbek, Ümmügül; Altan, Hakan; Department of Physics (2009)
In this thesis, we describe the development of a time-domain terahertz (THz) spectrometer driven by two different laser sources: an Er-doped femtosecond fiber laser and a mode-locked Ti:Sapphire laser. The resulting THz electromagnetic radiation was generated and detected using photoconductive antenna detection methods in both systems. In these experiments we characterized the THz power output for both the fiber laser driven system and the Ti:Sapphire laser driven system. Emphasis is given throughout this t...
The controlled drift detector as an x-ray imaging device for diffraction enhanced imaging
Özkan, Çiğdem; Serin, Meltem; Department of Physics (2009)
Diffraction Enhanced Imaging (DEI) is an X-ray imaging technique providing specific information about the molecular structure of a tissue by means of coherently scattered photons. A Controlled Drift Detector (CDD) is a novel 2D silicon imager developed to be used in X-ray imaging techniques. In this work a final (complete and detailed) analysis of DEI data taken with the CDD in the ELETTRA synchrotron light source facility in Trieste (Italy) in 2005, is presented and the applicability of both this new techn...
Localized surface plasmons in metal nanoparticles engineered by electron beam lithography
Güler, Urcan; Turan, Raşit; Department of Physics (2009)
In this study, optical behavior of metal nanoparticles having dimensions smaller than the wavelength of visible light is studied experimentally and numerically. Gold (Au) and silver (Ag) nanoparticles are studied due to their superior optical properties when compared to other metals. A compact code based on Discrete Dipole Approximation (DDA) is developed to compute extinction efficiencies of nanoparticles with various different properties such as material, dimension and geometry. To obtain self consistent ...
Citation Formats
M. Bektaş, “Fundamentals of a metal surface imaging system based on laser-optic principles,” M.S. - Master of Science, Middle East Technical University, 2009.