Person: Martínez Antón, Juan Carlos
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First Name
Juan Carlos
Last Name
Martínez Antón
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Óptica y Optometría
Department
Óptica
Area
Optica
Identifiers
3 results
Search Results
Now showing 1 - 3 of 3
Item Optical characterization of surfaces by robust reflectance determination based on air-gap interference(Applied Surface Science, 2004) Quiroga Mellado, Juan Antonio; Martínez Antón, Juan Carlos; González Moreno, RicardoIn this work we present an optical tool for characterizing the reflectance and polarimetric properties of surfaces. It uses only the image of the interference fringe pattern produced in a thin air-gap between the surface of interest and a glass surface acting as a reference. From only the contrast of the fringe pattern captured with a CCD we may obtain the reflectance of the surface, no need of measuring a reference beam. By taking two images with polarized light, we may get then the polarized reflectance R_p and R_s, but also the ellipsometric magnitude Δ, simply as a phase shift between fringes in p and s polarization. A sample of silicon with a thin layer of thermally grown silica is used to test the method.Item Enhancement of surface inspection by Moiré interferometry using flexible reference gratings(Optics Express, 2001) Quiroga Mellado, Juan Antonio; Martínez Antón, Juan Carlos; Canabal Boutureira, Héctor Alfonso; Bernabéu Martínez, Eusebio; Álvaro Labajo, M.; Cortés Testillano, V.We have extended the use of shadow Moiré technique to be implemented in simple curved surfaces by using a flexible grating. Dynamic visual inspection of surface micro-damages is significantly favored by the use of well adapted pliable gratings compared to the use of flat reference gratings. The experimental set-up consists of a plastic foil with a printed Ronchi grating stretched between three points which adapts to any cylindrical or conical convex surface independently of the relative orientation grating/surface. Static quantification of defects profiles is also possible with an attached CCD camera. Visual detection of defects in the range of ~30 μm in depth is obtainable.Item Topographic optical profilometry by absorption in liquids(Optics Express, 2012) Quiroga Mellado, Juan Antonio; Martínez Antón, Juan Carlos; Alonso Fernández, José; Gómez Pedrero, José AntonioOptical absorbance within a liquid is used as a photometric probe to measure the topography of optical surfaces relative to a reference. The liquid fills the gap between the reference surface and the measuring surface. By comparing two transmission images at different wavelengths we can profile the height distribution in a simple and reliable way. The presented method handles steep surface slopes (<90 degrees) without difficulty. It adapts well to any field of view and height range (peak to valley). A height resolution in the order of the nanometer may be achieved and the height range can be tailored by adapting the concentration of water soluble dyes. It is especially appropriate for 3D profiling of transparent complex optical surfaces, like those found in micro-optic arrays and for Fresnel, aspheric or free-form lenses, which are very difficult to measure by other optical methods. We show some experimental results to validate its capabilities as a metrological tool and handling of steep surface slopes.