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Differentiating optical correlator
Optics Letters, 1995We introduce a new filter for an optical correlator that produces the spatial derivative of the optical correlation between an input object and a reference object. The derivative signal has a dark spot at the center of the correlation output. The width of this dark spot is narrower than the width of the conventional correlator bright spot and provides ...
J A, Davis +4 more
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Moiré optical spatial correlator
Optics Letters, 1984A new optical method to obtain the spatial-correlation integral of moiré maps is described and demonstrated. This method permits the direct and quantitative determination of the optical spatial correlation between two objects. The method can be applied to any optical quantity mapped by any moiré technique.
O, Kafri, T, Chin, D F, Heller
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Optical correlator tracking nonlinearity
Applied Optics, 1987Non linearite observee en utilisant un correlateur optique de Vanderlugt etalon comme poursuiveur de corps ...
D A, Gregory, J C, Kirsch, J L, Johnson
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Applied Optics, 1975
A real-time coherent optical correlator is described that uses the Itek PROM as a recyclable filter recording medium. Operation of a joint transform correlator is compared to a conventional Vander Lugt system. Experimental results are shown for the joint transform system, including demonstrations of the effects of target alignment and scale and the ...
P, Nisenson, R A, Sprague
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A real-time coherent optical correlator is described that uses the Itek PROM as a recyclable filter recording medium. Operation of a joint transform correlator is compared to a conventional Vander Lugt system. Experimental results are shown for the joint transform system, including demonstrations of the effects of target alignment and scale and the ...
P, Nisenson, R A, Sprague
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Applied Optics, 1973
A real-time optical correlator based on the principle of one-bit correlation, often used to facilitate the construction of real-time digital signal processors, is shown to have a greater immunity to mechanical noise than a comparable analog optical correlator.
G J, Aitken, D R, Carter
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A real-time optical correlator based on the principle of one-bit correlation, often used to facilitate the construction of real-time digital signal processors, is shown to have a greater immunity to mechanical noise than a comparable analog optical correlator.
G J, Aitken, D R, Carter
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New Multichannel Optical Correlator
Applied Optics, 1971This paper describes a multichannel optical correlator that uses two spatial dimensions to achieve multi-channel capability and operates in real time. Given I signals, r(i)(t), and J signals, s(j)(t), it can produce the I x J cross products, r(i)(t)s(j)(t), averaged over some interval.
G J, Aitken, L, Wang
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Optics Letters, 1981
The operation of a scanning optical correlator is described and demonstrated. The device is shown to combine the advantages of a coherent correlator, which makes preprocessing operations easy to realize, with the advantages of direct-image-casting correlators, which are insensitive to setup misalignment and imperfections and do not require the ...
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The operation of a scanning optical correlator is described and demonstrated. The device is shown to combine the advantages of a coherent correlator, which makes preprocessing operations easy to realize, with the advantages of direct-image-casting correlators, which are insensitive to setup misalignment and imperfections and do not require the ...
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Single Nanowire Optical Correlator
Nano Letters, 2014Integration of miniaturized elements has been a major driving force behind modern photonics. Nanowires have emerged as potential building blocks for compact photonic circuits and devices in nanophotonics. We demonstrate here a single nanowire optical correlator (SNOC) for ultrafast pulse characterization based on imaging of the second harmonic (SH ...
Huakang, Yu +7 more
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Compact planar optical correlator
Optics Letters, 1997A compact planar configuration for performing optical correlation is described. It comprises two pairs of identical holographic lenses and a holographic filter. Each pair of lenses is recorded on a single substrate; together the lenses perform exact Fourier transformation.
S, Reinhorn, Y, Amitai, A A, Friesem
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Incoherent Optical Correlators
SPIE Proceedings, 1990Optical correlators utilizing spatially incoherent light are examined and compared with coherent correlators. Frequency and image domain optical correlator architectures are discussed. The effect of speckle noise and input noise is examined. Simplified linear systems and Fourier transform descriptions of incoherent processors are provided.
David Casasent +2 more
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