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Système pour l'Observation de la Terre images are used to map ground displacements induced by earthquakes. Deformations (offsets) induced by stereoscopic effect and roll, pitch, and yaw of satellite and detector artifacts are estimated and compensated. Images are then resampled in a cartographic projection with a low-bias interpolator. A subpixel correlator(More)
' ERS SAR amplitude images are utilized to map ground displacements from a sub-pixel correlation method. It yields a _ground two-dimen sional displacement field with independent measurements about every 128m in azimuth · and 250m in range. The accuracy depends on the characteristics of tbe images. For the Landers test case, the 1-cr uncertainty is 0 .8m in(More)
The secondary structures of poly(dG-dC).poly(dG-dC) in the presence of alcaline , alcaline earth and first row transition metal ions (Na+, Mg2+, Co2+, Ni2+) are investigated by infrared spectroscopy. The conformational transitions are studied as a function of the hydration of the polynucleotide and counter-ion nature and content. The use of selectively(More)
We present an original and compact optical system inspired by the unusual eyes of a Strepsipteran insect called Xenos peckii. It is designed for a field of view of 30 degrees and is composed of multiple telescopes. An array of prisms of various angles is placed in front of these telescopes in order to set a different field of view for each channel. This(More)
In the first paper of this series, we proposed a definition for the concept of 2-D optical cellular processors. In this second part we present an optical experimental setup capable of implementing a binary pattern recognizer. A 2-D hologram array is used in conjunction with a multiplexed holographic illumination for the interconnection and makes the system(More)
We present a new method to measure the modulation transfer function (MTF) beyond the Nyquist frequency of a multichannel imaging system for which all the channels have parallel optical axes. Such a multichannel optical system produces a set of undersampled subimages. If the subimages contain nonredundant information, high spatial frequencies are folded(More)
Diffractive axicons are optical components producing achromatic nondiffracting beams. They thus produce a focal line rather than a focal point for classical lenses. This gives the interesting property of a long focal depth. We show that this property can be used to design a simple imaging system with a linear variable zoom by using and translating a(More)
Tolerance in angles of continuously self-imaging gratings (CSIGs) is explored. The degradation in angle of the shape of the point-spread function is theoretically investigated and illustrated by simulations and experiments. The formalism presented is inspired by the one used for classical lenses and can be easily generalized to diffraction gratings. It(More)