Results 141 to 150 of about 7,437 (194)

Low Coherence Interferometric Technique

2001
We propose an original technique based on low coherence interferometry to detect objects in strongly scattering media. In order to use broadband light, a special interferometer called the SISAM correlator is used to allow coherent superposition of the reference and tested beams.
G. Brun, I. Verrier, K. Ben Houcine, C. Veillas, J. P. Goure   +4 more
openaire   +1 more source

Contactless interferometric incremental measurement technique

Measurement, 1988
Abstract This paper presents a measurement technique which makes it possible to scan varying interference patterns by using the incremental procedure (forward-backward counting method). The essence of this procedure is that the primary interference pattern is scanned point-shaped (with a very small detector area) and in a locally identical way.
-Ing H.-J. Büchner, sc techn G. Jäger
openaire   +1 more source

A new interferometric alignment technique

Applied Physics Letters, 1977
A new interferometric alignment technique has been developed that is suitable for aligning x-ray lithography masks or photomasks relative to a substrate. A superposition precision of 200 Å has been demonstrated and in principle ∼100 Å should be possible.
D. C. Flanders, Henry I. Smith, Stewart Austin   +2 more
openaire   +1 more source

New absolute distance interferometric technique

SPIE Proceedings, 2004
We present a new method for the measurement of the absolute distance of a remote target based on the laser diode self-mixing interferometry technique, assisted by an electronic feedback loop capable of increasing the measurement accuracy. In this method, we use an electronic feedback loop to generate a wavelength change that exactly corresponds to one ...
S. Donati, G. Giuliani, NORGIA, MICHELE
openaire   +2 more sources

Specialized Interferometric Testing Techniques

Workshop on Optical Fabrication and Testing, 1981
With higher and higher demands put on the performance of optical systems today, there has been a trend toward using nonspherical surfaces in these systems. Optical metrology is given the responsibility for testing these surfaces. Fortunately, many of these surfaces can be tested in a straightforward manner.
openaire   +1 more source

Hologram repositioning by an interferometric technique

Applied Optics, 1979
An interferometric technique for hologram repositioning is described where the hologram is compared with the interference pattern of the reference and object waves. Analytical expressions to evaluate the accuracy of the repositioning are presented for the method. Two applications of the method in metrology for micromovement measurements are proposed.
openaire   +2 more sources

Imaging through scattering media by interferometric techniques

Applied Optics, 1981
Imaging through scattering media such as fog is a problem with few known viable solutions. Holographic techniques have been demonstrated successfully in the laboratory, but their usefulness is often limited in field conditions by the requirement of a separate coherent reference beam.
A M, Tai, C C, Aleksoff, B J, Chang
openaire   +2 more sources

Specialized Interferometric Testing Techniques

Workshop on Optical Fabrication and Testing, 1990
Summary not available.
openaire   +1 more source

Dual-wavelength interferometric technique with subnanometric resolution

Applied Optics, 2002
A new fringe subdivision method that employs a large synthetic wavelength to subdivide fringes formed by a small single wavelength is proposed. Based on this subdivision method, we demonstrate a novel dual-wavelength interferometric technique with subnanometric resolution, whose potential fringe subdivision factor derived from an evaluation of the ...
Benyong, Chen, Xiaohui, Cheng, Dacheng, Li   +2 more
openaire   +2 more sources

Advanced interferometric techniques for monitoring urban areas

2009 Joint Urban Remote Sensing Event, 2009
This paper addresses techniques for the imaging and monitoring of urban areas via advanced interferometric analysis. We discuss the multidimensional SAR imaging techniques and an approach for the generation of long term time series from multisensor data. Results of the application to real ERS and Envisat data are presented.
Bonano M, Fornaro G, Lanari R, Manunta M, Reale D, Serafino F   +5 more
openaire   +4 more sources