Now showing items 11-16 of 16
Logic operations by using modulated speckle
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 ...
Features on photorefractive registered speckles
The recording and read-out of a volume speckle pattern is investigated for transmission geometry. The modulation of the 3D speckle grains appears when the image of a coherently illuminated random diffusor is formed onto ...
Effect of the internal modulation of speckles in displacement measurements in optical vortex metrology
The Optical Vortex Metrology is based on the possibility of characterizing, through topological and morphological parameters, each one of the vortices existing in the phase of the optical field, or in a pseudo-phase obtained ...
Soap film analysis by speckle interferometer
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 ...
Double exposure specklegrams obtained by using scaled aperture pupils
In speckle photography the pupil aperture is usually not modified between exposures. In our work, the change of the pupil aperture scale between exposures is analyzed on the basis of double-exposed image speckle, before ...
Double aperture speckle method using a BSO crystal for in plane displacement
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 ...