Implementación del método de propagación para la toma de radiografías por contraste de fase de rayos X

Phase-contrast X-ray imaging is an alternative technique for taking X-rays which uses the property of phase of electromagnetic waves for improved contrast, especially at boundaries between materials of different densities. This thesis aimed to analyze the five most common methods used to apply phase-contrast X-ray imaging (propagation, interferometry, analyzer, differential, coded-aperture) and pick one of them to implement at Universidad de los Andes' High Energy Physics laboratory. The method of propagation was picked and studied thoroughly before starting the implementation. Using the parameters found in various references, a first version of the experimental setup was implemented, and through repeated X-ray tests it was improved and optimized until adequate parameters for the specific samples and conditions of the laboratory were obtained. Phase-contrast X-ray images were taken of mammographic phantoms, dry leaves, plates of different materials and insects. The results were analyzed and various methods of post-processing were proposed to enhance the phase effects in each particular image. A Beam Hardening Calibration and a Python algorithm were made to increase the contrast and quality of the images. Finally, a procedure was developed that allows the implementation of phase-contrast X-ray imaging using the method of propagation, that covers the selection of parameters, the acquisition of images, and their analysis and post-processing.

• Autores: Velásquez Moros, Andrea
• Tipo de recurso: Trabajo de grado de pregrado
• Fecha de publicación: 2017
• Institución: Universidad de los Andes
• Repositorio: Séneca: repositorio Uniandes
• Idioma: spa
• OAI Identifier: oai:repositorio.uniandes.edu.co:1992/61378
• Acceso en línea: http://hdl.handle.net/1992/61378
• Palabra clave: Rayos X; Tomografía computarizada por rayos X
• Rights: openAccess
• License: http://creativecommons.org/licenses/by-nc-sa/4.0/