Papers by Victor Ivan Moreno Oliva
CienciaUAT
Actualmente, existe un gran interés en el estudio de los sistemas de concentración de radiación s... more Actualmente, existe un gran interés en el estudio de los sistemas de concentración de radiación solar para el aprovechamiento de este recurso. Diversas geometrías, puntuales, lineales y de no enfoque, han sido usadas para la concentración de radiación solar. La cantidad de energía recolectada por estos sistemas es sensible a deformaciones en la superficie reflectora, por lo que se ha vuelto imprescindible el desarrollo de técnicas para el control de calidad. En este trabajo se desarrolló una técnica óptica basada en el método de triangulación láser, para la cual se utilizó la proyección de una línea de luz láser sobre la superficie a evaluar, una cámara perpendicular a un plano de referencia y el objeto de estudio. La técnica consiste en asociar los desplazamientos laterales de la línea láser, observados por la cámara, con los cambios de altura del objeto respecto al plano de referencia, a partir de un modelo matemático. Para conseguir una reconstrucción digital del objeto completo ...
Applied Optics
We study the formation of caustic surfaces produced by conic lenses, considering a plane wavefron... more We study the formation of caustic surfaces produced by conic lenses, considering a plane wavefront propagating parallel to the optical axis. The shape of the caustic can be modified by changing the parameters of the lens in such a way that if we are able to vanish the caustic, the optical system produces the sharpest diffraction-limited images. Alternatively, caustic surfaces with a large area can be applied to the design of non-imaging optical systems, with potential applications such as diffusers of light for illumination or solar concentrators. Here, we provide analytic equations for the conic constants, principal surfaces, and caustic surfaces, and also approximations at the third and fifth orders formed by conic lenses, in order to reduce the spherical aberration at these orders.
Fourier Transforms - High-tech Application and Current Trends, 2017
The harmonic content in electrical power systems is an increasingly worrying issue since the prol... more The harmonic content in electrical power systems is an increasingly worrying issue since the proliferation of nonlinear loads results in power quality problems as the harmonics is more apparent. In this paper, we analyze the behavior of the harmonics in the electrical power systems such as cables, transmission lines, capacitors, transformers, and rotating machines, the induction machine being the object of our study when it is excited to nonsinusoidal operating conditions in the stator winding. For this, a model is proposed for the harmonic analysis of the induction machine in steady-state regimen applying the Fourier transform. The results of the proposed model are validated by experimental tests which gave good results for each case study concluding in a model proper for harmonic and nonharmonic analysis of the induction machine and for "harmonic" analysis in an electrical power system.
AIP Conference Proceedings, 2008
In order to reduce the numeric errors accumulated during the integration procedure, a greater den... more In order to reduce the numeric errors accumulated during the integration procedure, a greater density of sampling is obtained reducing the spacing between spots in the integration paths selected, for this, a new design of the null screen is proposed, these design allow a two-dimensional point shifting (angular and radial) of the spots on the image plane by only the angular movement of the test surface. A screen for producing an image with spots ordered in a radial arrangement is used. Experimental results for the test of fast convex aspheric surface (F∕&mesh; = 0.22) are shown.
Actualmente, existe un gran interés en el estudio de los sistemas de concentración de radiación s... more Actualmente, existe un gran interés en el estudio de los sistemas de concentración de radiación solar para el aprovechamiento de este recurso. Diversas geometrías, puntuales, lineales y de no enfoque, han sido usadas para la concentración de radiación solar. La cantidad de energía recolectada por estos sistemas es sensible a deformaciones en la superficie reflectora, por lo que se ha vuelto imprescindible el desarrollo de técnicas para el control de calidad. En este trabajo se desarrolló una técnica óptica basada en el método de triangulación láser, para la cual se utilizó la proyección de una línea de luz láser sobre la superficie a evaluar, una cámara perpendicular a un plano de referencia y el objeto de estudio. La técnica consiste en asociar los desplazamientos laterales de la línea láser, observados por la cámara, con los cambios de altura del objeto respecto al plano de referencia, a partir de un modelo matemático. Para conseguir una reconstrucción digital del objeto completo ...
Solar Collectors and Panels, Theory and Applications, 2010
8th Iberoamerican Optics Meeting and 11th Latin American Meeting on Optics, Lasers, and Applications, 2013
ABSTRACT A method to design Ronchi-Hartmann null screens for improved alignment in the testing of... more ABSTRACT A method to design Ronchi-Hartmann null screens for improved alignment in the testing of fast concave conic mirrors is presented. The designs of these null screens are based on knowledge of the caustic by reflection.
Modeling Aspects in Optical Metrology II, 2009
In this work we report a method for testing a parabolic trough solar collector (PTSC) based on th... more In this work we report a method for testing a parabolic trough solar collector (PTSC) based on the null screen principles. For surfaces with symmetry of revolution a cylindrical null screen is used, now, for testing the PTSC we use a flat null screen. The design of the null screen with ellipsoidal spots is described; its image, which is formed by reflection on the test surface, becomes an exact square array of circular spots if the surface is perfect. Any departure from this geometry is indicative of defects on the surface. The flat null screen design and the surface evaluation algorithm are presented. Here the surface is tested in sections and the evaluation of the shape of the surface is performed with stitching method. Results of the evaluation for a square PTSC with 1000 mm by side (F/0.49) are shown.
8th Iberoamerican Optics Meeting and 11th Latin American Meeting on Optics, Lasers, and Applications, 2013
ABSTRACT In order to obtain a clearer interpretation of the Intensity Transport Equation (ITE), i... more ABSTRACT In order to obtain a clearer interpretation of the Intensity Transport Equation (ITE), in this work, we propose an algorithm to solve it for some particular wavefronts and its corresponding intensity distributions. By simulating intensity distributions in some planes, the ITE is turns into a Poisson equation with Neumann boundary conditions. The Poisson equation is solved by means of the iterative algorithm SOR (Simultaneous Over-Relaxation).
8th Iberoamerican Optics Meeting and 11th Latin American Meeting on Optics, Lasers, and Applications, 2013
ABSTRACT We report the qualitative testing of a spherical concave surface with deformation coeffi... more ABSTRACT We report the qualitative testing of a spherical concave surface with deformation coefficients based on the null-screen principles. The design of cylindrical null screen with curved grid is described; its image, which is formed by reflection on the test surface, becomes an exact square grid if the surface is perfect. Any departure from this geometry is indicative of defects on the surface. In contrast to others tests, here the whole surface is tested at once. The surface under test is 140 mm in diameter and a radius of curvature of 97 mm. The surface is testing during the manufacturing process; departures from the design surface will be analyzed and discussed.
22nd Congress of the International Commission for Optics: Light for the Development of the World, 2011
ABSTRACT The null-screen method has been used to test aspheric surfaces. This geometrical method ... more ABSTRACT The null-screen method has been used to test aspheric surfaces. This geometrical method measures the slope of the test surface and by a numerical integration procedure the shape of the test surface can be obtained. Now, in order to test the surfaces of a variable focal length lens (VFLL), we propose use a conical null-screen. We present the formulae to design the null-screen in such a way that the image on the CCD is a perfect array of spots; departures from this geometry are observed as deformation of the surface. The VFLL is designed in such a way that under conditions of mechanical equilibrium both surfaces are spherical; however, its shape can be easily modified mechanically changing its radius of curvature. In order to analyze the shape of the surfaces of the VFLL at different radius of curvature, we evaluate its form using a conical null-screen. This procedure allows study the deformations of the surface.
Applied Optics, 2006
The global optimization threshold algorithm is reported to obtain the deformations of an optical ... more The global optimization threshold algorithm is reported to obtain the deformations of an optical surface. The advantage of these types of algorithm is that they can be solved for the correlation problem presented in Seidel polynomials. We obtain the 2D deformations of a surface test with the transversal aberration along one direction only. In order to apply this algorithm we used exact ray tracing to simulate the transversal aberration adapting the same mathematical theory for the Ronchi test. The error obtained in sagitta recovering deformation was 1 m.
Applied Optics, 2008
A method for increasing the precision and sensitivity of the quantitative evaluation of fast asph... more A method for increasing the precision and sensitivity of the quantitative evaluation of fast aspheric surfaces through the null screen method is presented. This consists of applying small displacements to the cylindrical null screen along the optical axis. These movements allow a scan of the image spots over zones that with the analysis of a single image are more difficult to evaluate. The precision of the test is increased due to a greater density of sampling reducing the numerical errors during the integration. Results of the evaluation of an elliptical concave mirror on axis show that the numerical integration errors can be reduced from 20% for short paths to 80% for larger integration paths.
Applied Optics, 2009
We report the testing of a fast off-axis surface based on the null screen principles. Here we des... more We report the testing of a fast off-axis surface based on the null screen principles. Here we design a tilted null screen with drop shaped spots drawn on it in such a way that its image, which is formed by reflection on the test surface, becomes an exact square array of circular spots if the surface is perfect. Any departure from this geometry is indicative of defects on the surface. Here the whole surface is tested at once. The test surface has a radius of curvature of r ¼ 20:4 mm (F=0:206). The surface departures from the best surface fit are shown; in addition, we show that the errors in the surface shape are below 0:4 μm when the errors in the determination of the coordinates of the centroids of the reflected images are less than 1 pixel, and the errors in the coordinates of the spots of the null screen are less than 0:5 mm.
Applied Optics, 2011
A method for testing fast aspheric convex surfaces with dynamic null screens using LCDs is shown.... more A method for testing fast aspheric convex surfaces with dynamic null screens using LCDs is shown. A flat null screen is designed and displayed on an LCD monitor with drop-shaped spots in such a way that the image, which is formed by reflection on the test surface, becomes an exactly square array of circular spots if the surface is perfect. Any departure from this geometry is indicative of defects on the surface. Here the whole surface is tested at once. The position of the spots on the LCD can be changed in a dynamic way, to perform point-shifting of the image spots. The proposed procedure improves the dynamic point-shifting method. As has been shown previously, this process reduces the numerical error during the integration procedure, thereby improving the sensitivity of the test. The positioning accuracy for the screen spots is related to the LCD's spatial resolution. Results of the evaluation of a parabolic convex surface with f =# ¼ 0:22 are shown.
Applied Optics, 2011
We have reproduced quantitatively the technique commonly used in optical shop to evaluate surface... more We have reproduced quantitatively the technique commonly used in optical shop to evaluate surface error from comparison between experimental and simulated Ronchigrams. We used this procedure to evaluate, from Ronchigrams of any number of fringes, the curvature radius and/or conic constant of conic surfaces. The error function is calculated without using integration (numerical or polynomial) so the corresponding problems were avoided. Furthermore, when the error function is described with cubic splines, then the local errors are very well reproduced, which is not the case with the polynomial description. We have described the error functions with conical surfaces or with cubic splines, and for the best reproduction of experimental Ronchigram we used genetic algorithms.
Revista Mexicana de …, 2005
Se describe un instrumento de contactoóptico para reconstruir en 3D la sagita de superficies no r... more Se describe un instrumento de contactoóptico para reconstruir en 3D la sagita de superficies no reflectoras tanto cóncavas como convexas. El instrumento mide la sagita proyectando la imagen de una rendija sobre la superficie a evaluar. Para obtener la sagita en 3D el instrumento se traslada en la dirección X y la superficie de prueba gira a una velocidad angular constante. Se alcanza una resolución de hasta 2.5µm en Z y 1µm en X. Descriptores: Metrología; perfilometría. An instrument of optical contact is described to obtain the values of zagita in 3D of concave and convex nonreflecting surfaces. The system measure the zagita imaging a thin variable slit over the surface test. To obtain 3D information the instrument is translated in X direction and the surface test is rotated a constant angular velocity. With this system is reached a resolution of 2.5µm in Z and 1µm in X.
The null screen is a geometric method that allows the testing of fast aspherical surfaces, this m... more The null screen is a geometric method that allows the testing of fast aspherical surfaces, this method measured the local slope at the surface and by numerical integration the shape of the surface is measured. The usual technique for the numerical evaluation of the surface ...
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Papers by Victor Ivan Moreno Oliva