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Speckle photography with different pupils in a multiple-exposure scheme
(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 ...
Reduction of speckle noise in digital holography by using digital image processing
(ELSEVIER GMBH, URBAN & FISCHER VERLAG, 2005-01-01)
A fundamental problem in optical and digital holography is the presence of speckle noise in the reconstruction process. Many approaches have been carried out in order to overcome such a problem ranging from modifying the ...
Three-dimensional surface contouring of macroscopic objects by means of phase-difference images
(OSA, 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 ...
Analysis of vibrations in a plate using interferometric methods
(SPIE, 2004-10-21)
In this work some frequencies and modes of vibration of a thin plate were determined using interferometric methods like: real-time holographic interferometry, time-average holographic interferometry, digital speckle pattern ...
Logic operations by using modulated speckle
(SPIE, 2001-08-14)
An alternative image multiplexing technique is proposed. In the arrangement implemented, the input is imaged by introducing a multiple aperture pupil in the imaging lens. Then, the speckle pattern is modulated by several ...
Soap film analysis by speckle interferometer
(SPIE-INT SOC OPTICAL ENGINEERING, 2003-01-01)
In this paper a soap film is characterized by using a speckle interferometer. The arrangement consists of a double-exposure specklegram obtained through a double-aperture system, by introducing a wedge in front of one ...
DC term filtering techniques in digital holography
(SPIE, 2004-10-21)
In numerical hologram reconstruction like in optical holography, there exist different diffraction orders, which many times produce difficulties for the image visualizations. In numerical reconstruction, the filtering of ...
