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Double aperture speckle method using a BSO crystal for in plane displacement
(SPIE, 1999-07-06)
The possibility of using a BSO crystal as a recording medium of specklegrams with carrying frequency fringes, to storage multiple interferograms, for uniform in-plane displacements, is presented. Experimental results are ...
Contrast inversion in the Lau phenomena implemented with a photorefractive grating
(SPIE, 1999-07-06)
It was implemented the Lau effect with a grating registered in a BSO crystal. Two different arrangement were analyzed. In both cases, it is possible to control the visibility and to produce the contrast inversion of fringes, ...
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 ...
Speckle photography through different multiaperture pupils
(SPIE/ 18th Congress of the International Commission for Optics, 1999-07-19)
An image multiplexing method based on the internal modulation of speckle grains by employing different multiple aperture pupils for recording is proposed. The interferometric fringes profile and visibility in the Fourier ...
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 ...
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 ...
Talbot and Lau phenomena implementation via a photorefractive converter
(SPIE, 1999-07-06)
We propose a novel implementation of the Lau and Talbot effects. It employs a grating registered as modulation of birefringence in a Bi12SiO20 crystal. The systems proposed allow to control the visibility and in particular ...
Reduction of speckle noise in digital holography
(SPIE, 2004-10-21)
A fundamental problem in holography, as well optical as digital, is the presence of speckle noise in the reconstruction process -- Many approaches have been carried out in order overcome such a problem, ranging from altering ...
Photorefractive optical processing: some proposals
(SPIE, 1999-04-29)
Some proposals on Lau and Talbot fringes formation based on a grating registered as birefringence modulation in a photorefractive crystal, will be presented. In the Talbot case, the stored grating can be replicated if ...
Evaluation between methods for the color measurement in holograms by using a CMOS-RGB camera and a spectrometer
(SPIE, 2013-07-22)
Many models and methods commonly used in colorimetry have been incorporated to the study and knowledge of the colorimetric properties in the reflection color holograms; these methods have reported the possibilities of color ...
