Recent Submissions

  • Speckle interferometric technique to assess soap films 

    Ángel Toro, Luciano; Bolognini, Néstor Alberto; Tebaldi, Myrian Cristina; Trivi, Marcelo Ricardo (Elsevier B.V., 2003-10-17)
    An speckle interferometric technique to monitor the thinning process of vertical soap film before the film rupture is presented -- The interferometric arrangement consists in a double aperture pupil optical system which ...
  • Speckle photography with different pupils in a multiple-exposure scheme 

    Ángel Toro, Luciano; Bolognini, Néstor Alberto; Tebaldi, Myrian Cristina; Trivi, Marcelo Ricardo (Optical Society of America, 2000-01-01)
    The use of different multiple-aperture pupils for recording each image in speckle photography is proposed -- The introduction of suitable spatial frequency carriers, by internally modulating imaged speckles, allows one to ...
  • Obtención de estructuras de relieve en materiales de registro de haluros de plata 

    Velásquez Prieto, Daniel; Giraldo Castaño, Lady Marcela (Sedoptica; Grupo de Investigación de Óptica Aplicada; Escuela de Ciencias y Humanidades, 2013-09-19)
    Diffraction transmission gratings were recorded in AGFA-8E75 film, chemically treated under processes with D-19 + potassium ferrocyanide and a chemical processing technique proposed for PE-2 film to obtain embossed stripes. ...
  • Shack - Hartmann spot dislocation map determination using an optical flow method 

    Vargas, Javier; Restrepo Gómez, René; Belenguer, Tomás (OSA; Escuela de Ciencias y Humanidades, 2014-01-14)
    We present a robust, dense, and accurate Shack-Hartmann spot dislocation map determination method based on a regularized optical flow algorithm that does not require obtaining the spot centroids. The method is capable to ...
  • Improvement of the signal-to-noise ratio in digital holography 

    Velásquez-Prieto, Daniel; Herrera Ramírez, Jorge Alexis; García Sucerquia, Jorge Iván (Sociedad Mexicana de Física; Grupo de Investigación de Óptica Aplicada; Escuela de Ciencias y Humanidades, 2005-02)
    A fundamental problem in optical and digital holography is the presence of speckle noise in the reconstruction process, which essentially diminishes the signal to noise ratio (SNR). For many applications, that reduction ...
  • Three-dimensional contouring with digital holography 

    Velásquez-Prieto, Daniel; García Sucerquia, Jorge Iván (Sociedad Colombiana De Física; Grupo de Investigación de Óptica Aplicada; Escuela de Ciencias y Humanidades, 2005-04-28)
    We report on a technique to determine the 3D contour of objects with dimensions of at least four orders of magnitude larger than the illumination optical wavelength. Our proposal is based on the numerical reconstruction ...
  • Three-dimensional surface contouring of macroscopic objects by means of phase-difference images 

    García Sucerquia, Jorge Iván; Velásquez Prieto, Daniel Ignacio (OSA; Grupo de Investigación de Óptica Aplicada; Escuela de Ciencias y Humanidades, 2006-04-16)
    We report a technique to determine the 3D contour of objects with dimensions of at least 4 orders of magnitude larger than the illumination optical wavelength. Our proposal is based on the numerical reconstruction of the ...
  • Multiple-aperture speckle method applied to local displacement measurements 

    Ángel-Toro, Luciano; Tebaldi, Myrian; Bologninic, Néstor (Elsevier B.V; Grupo de Investigación de Óptica Aplicada; Escuela de Ciencias y Humanidades, 2007)
    The goal of this work is to analyze the measurement capability of the modified speckle photography technique that uses different multiple aperture pupils in a multiple exposure scheme. In particular, the rotation case is ...
  • Propierties of speckle patterns generated through multiaperture pupils 

    Ángel-Toro, Luciano; Tebaldi, Myrian; Trivi, Marcelo; Bolognini, Néstor (Elsevier; Grupo de Investigación de Óptica Aplicada; Escuela de Ciencias y Humanidades, 2001-05-15)
    The characteristics of the image speckles obtained through multiple aperture pupils are theoretically analyzed in terms of the parameters defining the pupils. The possibility of interpreting and synthesizing the image ...
  • Multiple rotation assessment through isothetic fringes in speckle photography 

    Ángel-Toro, Luciano; Tebaldi, Myrian; Bolognini, Néstor (OSA; Grupo de Investigación de Óptica Aplicada; Escuela de Ciencias y Humanidades, 2007-04-20)
    The use of different pupils for storing each speckled image in speckle photography is employed to determine multiple in-plane rotations. The method consists of recording a four exposure specklegram where the rotations are ...
  • Optical processing by fringed speckles registered in a BSO crystal 

    Tebaldi, Myrian; Trivi, Marcelo; Bolognini, Néstor; Ángel-Toro, Luciano (SPIE; Grupo de Investigación de Óptica Aplicada; Escuela de Ciencias y Humanidades, 2000-07-28)
    An alternative image multiplexing technique, employing a multiple-aperture pupil for each exposure, is presented. The aperture arrangement of the pupil is modified between exposures. A thick photorefractive BSO crystal is ...
  • Phase stepping in Lau interferometry 

    Ángel-Toro, Luciano; Tebaldi, Myrian; Henao, Rodrigo (Elsevier; Grupo de Investigación de Óptica Aplicada; Escuela de Ciencias y Humanidades, 1999-06-15)
    The implementation of phase shifting interferometry to analyze the Lau interferometric fringe patterns is proposed. The fundamentals of this application are theoretically discussed and the basis of the phase map interpretation ...
  • New multiple aperture arrangements for speckle photography 

    Angel-Toro, Luciano; Tebaldi, Myrian; Trivi, Marcelo; Bolognini, Néstor (Elsevier B.V; Grupo de Investigación de Óptica Aplicada; Escuela de Ciencias y Humanidades, 2000-08-01)
    Abstract. We propose a multiple exposure specklegram by using an optical system whose multiple aperture pupil changes between exposures. In particular, we analyze experimentally two arrangements and we show that it is ...
  • Phase-object detection by use of double-exposure fringe-modulated speckle patterns 

    Tebaldi, Myrian; Trivi, Marcelo; Bolognini, Néstor; Angel-Toro, Luciano (OSA; Grupo de Investigación de Óptica Aplicada; Escuela de Ciencias y Humanidades, 2003-01)
    We study the properties of a double-exposure image specklegram of a diffuse object obtained by use of a doubleaperture pupil. A phase object is placed in front of one aperture during the first or the second exposure. Also, ...
  • Obtención de estructuras de relieve en materiales de registro de haluros de plata 

    Giraldo, L.M; Velásquez, D. (Sociedad Española de Óptica; Grupo de Investigación de Óptica Aplicada; Escuela de Ciencias y Humanidades, 2013-01)
    Diffraction transmission gratings were recorded in AGFA-8E75 film, chemically treated under processes with D-19 + potassium ferrocyanide and a chemical processing technique proposed for PE-2 film to obtain embossed stripes. ...
  • Vortex metrology using Fourier analysis techniques: vortex networks correlation fringes 

    Ángel Toro, Luciano; Sierra Sosa, Daniel; Tebaldy, Myrian; Bolognini, Néstor (OSA; Grupo de Investigación de Óptica Aplicada; Escuela de Ciencias y Humanidades, 2012-10-19)
    In this work, we introduce an alternativemethod of analysis in vortexmetrology based on the application of the Fourier optics techniques. The first part of the procedure is conducted as is usual in vortexmetrology for ...
  • In-plane displacement measurement in vortex metrology 

    Angel-Toro, Luciano; Sierra-Sosa, Daniel; Tebaldi, Myrian; Bolognini, Néstor (Grupo de Investigación de Óptica Aplicada; Escuela de Ciencias y Humanidades, 2013-10-09)
    Recently we proposed an alternative method of displacement analysis in vortex metrology, based on the application of the Fourier optics techniques, that is suitable for an intermediate range of displacement measurements ...