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Estudio de la resistividad del material en base de FeCl3 para registros holográficos

ROSAURA VALLEJO MENDOZA (2012)

Se analizan las propiedades eléctricas de las películas orgánicas fotosensibles de volumen,

partiendo de dos matrices fotosensibles para uso holográfico; nitrocelulosa y PVA.

Ambas dopadas con FeCl3, comúnmente utilizando como fotosensibilizador. Con la técnica

de cuatro puntas, se mide la resistividad de estas matrices, para evitar los efectos iónicos

en la interface de material-electrodo, debido a que la película presenta un carácter

hidrofílico, con la matriz de PVA, e hidrofóbico con la matriz de nitrocelulosa.

Master thesis

Holographic interferometry Resistance measurement Polymers CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ÓPTICA

Regularized quadratic cost function for oriented fringe-pattern filtering

José de Jesús Villa Hernández JOSE ISMAEL DE LA ROSA VARGAS (2009)

We use the regularization theory in a Bayesian framework to derive a quadratic cost function for denoising

fringe patterns. As prior constraints for the regularization problem, we propose a Markov random field

model that includes information about the fringe orientation. In our cost function the regularization term

imposes constraints to the solution (i.e., the filtered image) to be smooth only along the fringe’s tangent direction.

In this way as the fringe information and noise are conveniently separated in the frequency space,

our technique avoids blurring the fringes. The attractiveness of the proposed filtering method is that the

minimization of the cost function can be easily implemented using iterative methods. To show the performance

of the proposed technique we present some results obtained by processing simulated and real fringe

patterns.

Producción Científica de la Universidad Autónoma de Zacatecas UAZ

Article

CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA digital fringe patterns holographic interferometry fringe patterns

Measurements of concentration differences between liquid mixtures using digital holographic interferometry

CARLOS ALBERTO OLVERA OLVERA Ma. Auxiliadora Araiza Esquivel (2017)

We present an alternative method to detect and measure the concentration changes in liquid solutions. The method uses Digital Holographic Interferometry (DHI) and is based on measuring refractive index variations. The first hologram is recorded when a wavefront from light comes across an ordinary cylindrical glass container filled with a liquid solution. The second hologram is recorded after slight changing the liquid’s concentration. Differences in phase obtained from the correlation of the first hologram with the second one provide information about the refractive index variation, which is directly related to the changes in physical properties related to the

concentration. The method can be used − with high sensitivity, accuracy, and speed − either to detect adulterations or to measure a slight change of concentration in the order of 0.001 moles which is equivalent to a difference of 0.003 g of sodium chloride in solutions. The method also enables to measure and calculate the phase difference among each pixel of two samples. This makes it possible to generate a global measurement of the phase difference of the entire sensed region.

Producción Científica de la Universidad Autónoma de Zacatecas UAZ

Article

INGENIERÍA Y TECNOLOGÍA Digital Holographic Interferometry refractive index measurements phase difference full-field measurements

Real-time measurement of the average temperature profiles in liquid cooling using digital holographic interferometry

CARLOS ALBERTO OLVERA OLVERA Ma. Auxiliadora Araiza Esquivel (2016)

We present an alternative optical method to estimate the temperature during the cooling process of a liquid using digital holographic interferometry (DHI). We make use of phase variations that are linked to variations in the refractive index and the temperature property of a liquid. In DHI, a hologram is first recorded using an object beam scattered from a rectangular container with a liquid at a certain reference temperature. A second hologram is then recorded when the temperature is decreased slightly. A phase difference between the two holograms indicates a temperature variation, and it is possible to obtain the temperature value at each small point of the sensed optical field. The relative phase map between the two object states is obtained simply and quickly through Fourier-transform method. Our experimental results reveal that the temperature values measured using this method and those obtained with a thermometer are consistent. We additionally show that it is possible to analyze the heat-loss process of a liquid sample in dynamic events using DHI. (C) 2016 Society of Photo-Optical Instrumentation Engineers (SPIE)

Producción Científica de la Universidad Autónoma de Zacatecas UAZ

Article

INGENIERÍA Y TECNOLOGÍA digital holographic interferometry refractive index difference liquids temperature phase difference

MICRO DEFORMATION STUDY ON INSECT'S WINGS USING HIGH SPEED DIGITAL HOLOGRAPHIC INTERFEROMETRY

Daniel D. Aguayo (2012)

"The research work presented in this thesis shows a successful and promising application of an optical non destructive testing technique known as Digital Holographic Interferometry (DHI). DHI is applied to detect and obtain deformations from butterflies’ wings during flapping motion; this generates displacement maps for the whole wings surface.

The in-vivo tests and their corresponding results were recorded for five different winged butterfly species. The first part of this research work, presents the measurement performed on wings from a Pterourus Multicaudata known as Eastern Swallow Tiger Butterfly, as a proof of principle that fast non repeatable events on organic tissues can be detected with high accuracy using DHI. The second part of this work presents a comparison from four different specimens, namely Nymphalis Antiopa known as Mourning Cloak, Agraulis Vanillae Incarnata known as Gulf fritillary, Danaus Gilippus Cramer and Precis Evarete Felder known as Queen Butterfly and Buckeye Butterfly respectively. All of them have a different structure and wing shape.

The DHI optical set up used has an out of plane sensibility that enables to measure changes perpendicular to the wings surface with hundreds of nanometers resolution. The wings motion is recorded with a high speed camera at rates of 500 frames per second for the proof of principle test, and 4000 frames per second for the remaining tests. The camera uses CMOS technology with 800 x 800 pixels resolution and dynamic range of 10 bits; features that allow the detection of small changes during wings flapping. The wing deformation maps are presented in a pseudo 3D representation, and they show the relative deformation of the insect’s wing for a fraction of time during the up and down stroke movements. A time vs. displacement tracking plot of randomly chosen wing sections is presented to show the differences of behaviour among different wing sections of a butterfly during normal flapping."

Doctoral thesis

DIGITAL HOLOGRAPHIC INTERFEROMETRY, INTEFEROMETERS, SPECKLE PATTERN INTERFEROMETRY, BUTTERFLY BACKGROUND, MORPHOLOGY CONCEPTS, OPTICAL PHASE, FOURIER TRANSFORM METHOD CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ÓPTICA HOLOGRAFÍA

STUDY OF SURFACE MECHANICAL PARAMETERS ON COMPOSITE BIOLOGICAL STRUCTURES BY USING NON-DESTRUCTIVE OPTICAL TESTS

Cesar Tavera (2019)

"In this thesis we report a study on cortical bones by means of the analysis of their surface displacement maps. We use Digital Holographic Interferometry (DHI), a powerful non-destructive optical testing for quantifying micrometric deformations. The bone samples are considered as a biological composite material with anisotropic properties, and as a consequence, with no linear behavior that implies a no repeatable mechanical response, even under the same mechanical excitation signals. This study is divided in two stages; first, cortical bone samples are extracted from porcine femoral diaphysis and cutted into cylinders that match the flat supports of a mechanical press in order to transmit compression loads in the physiological and overload ranges. By using a medical procedure to drill the samples, it was possible to compare the effect of bone loss volume and observe the microfractures presence around the perforations against to those non-drilled samples which were used as reference control. The results show a relationship between bone loss and compression loads that can be assumed as “lower compression values and fewer drillings create higher surface displacements, while higher compression values and more cortical drillings result in smaller surface displacements”; an opposite performance of isotropic materials. This section also proves that the high resolution of DHI gives a better understanding about the bone’s microstructural modifications, making it a viable ex-vivo technique to analyze the consequences of some medical procedures. The second section of the study aims to analyze the effect in bone strength when its organic and inorganic components are degraded independently, which simulates bone illness conditions, permitting to unveil their particular role in bone mechanical response. By employing FT-IR spectral signal in transmittance it was possible to validate the effects of demineralization and air-drying procedures implemented on cortical bovine samples that were machinated for compression tests. As in the previous stages, DHI was employed to calculate the amplitude and phase information from the cortical bone samples when are compressed under controlled loads in the physiologic and overload ranges."

Doctoral thesis

Holography Interferometry Bone Drilling Non-destructive Optical Tests Composite material deformations Bone Strength CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ÓPTICA HOLOGRAFÍA HOLOGRAFÍA

Análisis y aplicaciones del interferómetro con filo de la navaja: lentes con sistema 2f, y superficies cóncavas reflectoras

Efrén Santamaría Juárez (2019)

This thesis work continues with the implementation of the Knife Edge Interferometer (KEI), using the configuration 2f to measure the optical quality of lenses and spherical and parabolic concave reflective surfaces; eliminating the collimator system previously used, so that this system becomes an economical and versatile one; since we only require a knife to produce the wavefront by diffraction of the edge of the razor’s edge, and the test wavefront from the elements under test. This interferometer is classified as common trajectories, with self-reference, similar to the Linnik interferometer (IDP). Obtaining the interferograms using the KEI are partial due to the obstruction of the knife, so the method we use to obtain the remaining part, is rotating the knife 180°. Once the remaining part is obtained, we join the two partial interferograms by means of stitching them with computer programs from Matlab, thus obtaining the complete interferogram. Subsequently we analyze the interferograms using the commercial APEX program, obtaining quantitative results on the optical quality from the values of the aberrations, in terms of the wavelength of the light source used.

En este trabajo de tesis se continúa con la implementación del Interferómetro Filo de la Navaja (IFN), empleando el arreglo 2f para medir la calidad óptica de lentes y superficies reflectoras cóncavas esféricas y parabólicas; eliminando el sistema colimador empleado previamente, por lo que éste sistema se convierte en uno económico y versátil; ya que solo requerimos de una navaja para producir el frente de onda de referencia mediante la difracción del borde del filo de la navaja, y el frente de onda de prueba procedente de los elementos bajo prueba. Éste interferómetro se clasifica como de trayectorias comunes, con auto referencia, similar al interferómetro de Linnik (IDP). La obtención de los interferogramas empleando el IFN son parciales debido a la obstrucción de la navaja, por lo que el método que empleamos para obtener la parte restante, es rotando la navaja 180°. Una vez obtenida la parte restante, unimos los dos interferogramas parciales por medio del hilvanado de ellos con el programa de computadora Matlab, obteniendo así el interferograma completo. Posteriormente analizamos los interferogramas usando el programa comercial APEX, obteniendo resultados cuantitativos sobre la calidad óptica a partir de los valores de las aberraciones, en términos de la longitud de onda de la fuente de luz empleada.

Doctoral thesis

Testing lens and reflecting concave surface Interferometry Optical metrology CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ÓPTICA ÓPTICA

Implementación de transmitancias complejas con un modulador de amplitud electro-óptico

MARIA GUADALUPE MENDEZ VAZQUEZ (2007)

En esta tesis se presentan hologramas de amplitud generados por computadora que codifican funciones complejas arbitrarias y que son implementados experimentalmente con un modulador de cristal líquido que provee modulación de amplitud. Los hologramas propuestos permiten la síntesis de campos complejos con gran exactitud. Primero, se proponen hologramas de amplitud modificados con función de transmitancia obtenida a través de una adecuada función de fondo que acompaña al coseno del holograma de la señal codificada. La primera función de fondo propuesta s la envolvente suave del módulo de la señal codificada, la cual es apropiada para hologramas implementados en un modulador de amplitud sin fase acoplada. La segunda función de fondo propuesta, adecuada para la modulación de amplitud con fase acoplada, es una función constante. Por otra parte, el efecto no deseado producido por la pixelización del modulador se compensa usando un prefiltraje digital de la señal compleja codificada. Para ilustrar el desempeño de los hologramas diseñados, se sintetizan numéricamente diferentes campos ópticos tales como los haces de Bessel y de Laguerre-Gauss. Además, se realiza un análisis de la eficiencia y de la razón señal a ruido. Finalmente, se implementan experimentalmente hologramas que codifican haces Bessel de diferentes ordenes empleando una pantalla de cristal líquido que provee modulación de amplitud con fase acoplada mínima.

Master thesis

Holography Optical modulation Interferometry CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ÓPTICA OPTICA GEOMÉTRICA

Antennas for millimeter-wave applications

LUZ KARINE SANDOVAL GRANADOS (2016)

Migration of wireless systems to millimeter wave frequencies requires cost reduction solutions that take advantage of the compact size, high bandwidth and extreme data rates that a high frequency operation offers. New materials with better mechanical, thermal and electrical properties are now available; fabrication processes have reached nanometric resolutions and depending on the antenna’s type, different properties can be enhanced. Multiple applications had been created around this technology, internet of things, imaging technology, biomedical applications and interferometry radars base its operation in this technology.

Doctoral thesis

Millimeter wave Antennas Interferometry INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS TECNOLOGÍA DE LAS TELECOMUNICACIONES

PULSED ELECTRONIC SPECKLE PATTERN INTERFEROMETRY (ESPI)

Bernardino Barrientos (1999)

"A novel Electronic Speckle Pattern Interferometry, ESPI, technique is presented in this work. The technique consist of an out-of-plane interferometer which incorporates a specially fabricated computer-generated hologram. This hologram allows us to achieve spatial phase stepping and therefore analysis of transient phenomena becomes feasible. The advantage of this technique is the calculation of deformation by means of a double exposure method where no changes of any kind are necessary to be introduced between consecutive recordings".

Doctoral thesis

Interferometry Holography Spatial phase-stepping ESPI CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ÓPTICA ÓPTICA