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
5 results
Search Results
Now showing 1 - 5 of 5
Item Classification of surface structures on fine metallic wires(Applied Surface Science, 2001) Bernabeu Martínez, Eusebio; Sánchez Brea, Luis Miguel; Siegmann, Philip; Martínez Antón, Juan Carlos; Gómez Pedrero, José Antonio; Wilkening, Günter; Koenders, Ludger; Müller, Franz; Hildebrand, M.; Hermann, HartiIn this report a classification of the main surface structures found on fine metallic wires is carried out (between ∼20 and 500 μm in diameter). For this, we have analyzed a series of wires of different metallic materials, diameters and production environments by scanning electron microscopy, atomic force microscopy, and confocal microscopy. A description and the images of the structures is given and, in addition, a nomenclature to be used by manufacturers, customers and researches is proposed. With this information the surface quality of fine metallic wires may be improved in a fabrication level. One of the objectives of this catalogue of defects is to serve as a basis for measuring the quality of the surface of the wires during the production process and the development of a measuring device for that purpose.Item Diffraction in wide slits with semi-cylindrical edges(Optik, 2002) Siegmann, Philip; Sánchez Brea, Luis Miguel; Martínez Antón, Juan Carlos; Bernabeu Martínez, EusebioWe present an analytical model to obtain the diffraction pattern in far field of a metallic, thick slit based on the Geometrical Theory of Diffraction. The edges of the slit are modelled as semicylinders. We have considered that the thickness of the slit is sufficiently small compared to the width, so that the influence of multiple reflections between the edges may be neglected. The material in which the slit is made, as well as the polarization and angle of the incident beam, are considered. Notorious differences are obtained when compared to the classical diffraction from flat slits.Item In-line detection and evaluation of surface defects on thin metallic wires(Optical Measurement Systems for Industrial Inspection II: Applications in Production Engineering, 2001) Martínez Antón, Juan Carlos; Siegmann, Philip; Sánchez Brea, Luis Miguel; Gómez Pedrero, José Antonio; Canabal Boutureira, Héctor Alfonso; Bernabéu Martínez, Eusebio; Hoefling, Roland; Jueptner, Werner P. O.; Kujawinska, MalgorzataWe have developed a prototype for in-line detection of surface defects in metallic wires, specially for scratches. A simple geometrical relationship between surface topography and conical reflection, permits to correlate the defects with intensity patterns in a simple way. The presented apparatus consists basically in a grating-divided laser beam incident on angular equidistant points. A CCD and an associated optics capture the information of the whole wire perimeter at once. Analytic rudiments are provided in agreement with the experimental results.Item Static and dynamic detection of axial surface defects on metallic wires by conical triple laser reflection(Optics and Lassers in Engineering, 2004) Siegmann, Philip; Martínez Antón, Juan Carlos; Bernabeu Martínez, EusebioThe quality of the surface of metallic wires is relevant for different applications. The reflection of a laser beam on the surface of a metallic cylindrical wire provides an efficient way to inspect the quality of its surface. Our interest is focused in the detection of axially oriented defects, which are the most relevant for the wire drawing process. We present a simple interference-geometrical model to describe the light pattern reflected from a wire with defects. This model adequately accounts for the observed results from an industrial prototype developed for the purpose. It incorporates three-laser beams incident on the wire at equidistant locations in its perimeter, which produce three reflection cones with a CCD. This configuration permits to explore the whole perimeter of the wire. Several results are presented, both in static operation and in production line, in agreement with qualitative and quantitative predictions.Item Comparison between optical techniques and confocal microscopy for defect detection on thin wires(Applied Surface Science, 2004) Siegmann, Philip; Sánchez Brea, Luis Miguel; Martínez Antón, Juan Carlos; Bernabeu Martínez, EusebioConventional microscopy techniques, such as atomic force microscopy (AFM), scanning electron microscopy (SEM), and confocal microscopy (CM) are not suitable for on-line surface inspection of fine metallic wires. In the recent years, some optical techniques have been developed to be used for those tasks. However, they need a rigorous validation. In this work, we have used confocal microscopy to obtain the topography z(x,y) of wires with longitudinal defects, such as dielines. The topography has been used to predict the light scattered by the wire. These simulations have been compared with experimental results, showing a good agreement.