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SPIE Proceedings, 1989
In the past 15 years, a dozen or so designs have been proposed for compact optical correlators. Of these, maybe one-third of them have actually been built and only a few of those tested. This paper will give an overview of some of the systems that have been built as well as mention some promising early and current designs that have not been built.
Don A. Gregory, James C. Kirsch
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In the past 15 years, a dozen or so designs have been proposed for compact optical correlators. Of these, maybe one-third of them have actually been built and only a few of those tested. This paper will give an overview of some of the systems that have been built as well as mention some promising early and current designs that have not been built.
Don A. Gregory, James C. Kirsch
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SPIE Proceedings, 1990
A nonconventional setup based on the Lau effect is employed for implementing a lensless incoherent correlator of 2-D signals with compact support.
Pedro Andres +3 more
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A nonconventional setup based on the Lau effect is employed for implementing a lensless incoherent correlator of 2-D signals with compact support.
Pedro Andres +3 more
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Optical Correlators: Applications
2015Optical correlators (OCs) have received much attention since VanderLugt’s invention in the mid-1960s, when he showed that pattern recognition can be optically realized using matched spatial filtering techniques. The classical VanderLugt correlator used photographic plates or film for carrying both pieces of information: the input and the reference, in ...
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Incoherent optical correlators
Proceedings of the IEEE, 1977The use of optical systems in signal processing applications can offer significant advantages over an equivalent electronic approach. These advantages stem chiefly from the high-speed analog multiply and parallel processing capability inherent in an optical system. This can be used to advantage in application areas requiring large quantities of data to
M.A. Monahan, K. Bromley, R.P. Bocker
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Miniaturized optical correlator
SPIE Proceedings, 1990A robust optical correlator that is a miniaturized version of the classic Vander-Lugt correlator is developed. The correlator consists of a simple diode laser for illumination and a CMOS photodetector to detect the correlation peak. A set of roof prisms is configured to fold the light path into a compact design.
Marija Strojnik +4 more
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Annual Meeting Optical Society of America, 1988
A nonlinear joint transform image correlator is investigated. The Fourier transform interference intensity is thresholded to provide higher correlation peak intensity and a better defined correlation spot. Analytical expressions for the thresholded interference intensity are provided.
Bahram Javidi +2 more
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A nonlinear joint transform image correlator is investigated. The Fourier transform interference intensity is thresholded to provide higher correlation peak intensity and a better defined correlation spot. Analytical expressions for the thresholded interference intensity are provided.
Bahram Javidi +2 more
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1985
This chapter addresses the principles, architectures and performance of acousto-optic correlator systems. Two specific applications which might benefit from these devices are considered, namely spread-spectrum signal processing and lidar ambiguity-function processing.
R. Bowman, P. V. Gatenby, R. J. Sadler
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This chapter addresses the principles, architectures and performance of acousto-optic correlator systems. Two specific applications which might benefit from these devices are considered, namely spread-spectrum signal processing and lidar ambiguity-function processing.
R. Bowman, P. V. Gatenby, R. J. Sadler
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Two-focal-length optical correlator
Applied Optics, 1989A two-focal-length coherent optical correlator design is presented that uses simple, single element lenses. Experimental autocorrelation results using a binary phase-only filter verify the performance of this compact design.
J L, Horner, C K, Makekau
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Intelligent Optical Correlator
Optical Engineering, 1989By extracting the basic rectangular features of an object from a digitized Fourier transform image, one can calculate the scale factor and rotational angle of a rectangular object and use them to derotate and scale the input image. Thus, a scale- and rotational-invariant optical correlator is achieved. The accuracy of the computed scale and orientation
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Phase correlations and optical coherence
Optics Letters, 2012We examine the properties of the recently introduced degrees of coherence regarding the phase correlations of the optical field. It is seen that some of these quantities are straightforwardly related to the limits of complete dependence and complete independence of phases, which were used as the extremes of complete coherence and complete incoherence ...
Jani, Tervo +2 more
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