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Coherent diffractive imaging and partial coherence
Physical Review B, 2007We formulate coherent diffractive imaging in the framework of partially spatially coherent diffraction. We find that the reconstruction can be critically dependent on the degree of coherence in the illuminating field and that even a small departure from full coherence may invalidate the conventional assumption that a mapping exists between an exit ...
Williams, Garth J. +3 more
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Noise Suppression in Coherent Imaging
Applied Optics, 1973Several noise suppression techniques in coherent imaging systems are described. For holographic imaging the diffuse wave, periodic phase modulation, and multiple wave techniques are compared and the implementation of the last is considered. For lens-type imaging systems the use of multiple incoherent waves results in excellent noise suppression.
J, Upatnieks, R W, Lewis
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Chrono-coherent imaging for medicine
IEEE Transactions on Biomedical Engineering, 1989We describe a new method for imaging with visible and near visible light inside media, such as tissues, which have strong light scattering. The chrono-coherent imaging (CCI) method is demonstrated in this paper for a transmission geometry where an absorbing object is completely hidden from normal visual observation by light scattering of the media. The
K G, Spears +4 more
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Journal of the Optical Society of America A, 2012
This paper defines a matrix from which coherence property of imaging by partially coherent Koehler illumination is determined. The matrix termed coherency matrix in imaging system is derived by the space average of a product of a column vector and its transpose conjugate where each row of the column vector represents mutually incoherent light.
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This paper defines a matrix from which coherence property of imaging by partially coherent Koehler illumination is determined. The matrix termed coherency matrix in imaging system is derived by the space average of a product of a column vector and its transpose conjugate where each row of the column vector represents mutually incoherent light.
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Dual-channel inline coherent imaging
Applied Optics, 2019We present a dual-channel inline coherent imaging system for laser machining monitoring using a single spectrometer. Sensitivity enhancement due to the added signal of the two input channels is demonstrated with a maximum sensitivity of 99 dB at a 73 kHz acquisition rate.
Faleh, Altal +4 more
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Dynamic sample imaging in coherent diffractive imaging
Optics Letters, 2011As the resolution in coherent diffractive imaging improves, interexposure and intraexposure sample dynamics, such as motion, degrade the quality of the reconstructed image. Selecting data sets that include only exposures where tolerably little motion has occurred is an inefficient use of time and flux, especially when detector readout time is ...
Jesse N, Clark +7 more
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Coherent compounding in doppler imaging
IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, 2015Coherent compounding can provide high frame rates and wide regions of interest for imaging of blood flow. However, motion will cause out-of-phase summation, potentially causing image degradation. In this work the impact of blood motion on SNR and the accuracy of Doppler velocity estimates are investigated.
Ingvild K, Ekroll +4 more
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Imaging Systems, 2010
Coherent imaging has numerous advantages over incoherent imaging, but at a cost of requiring coherent laser illumination.
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Coherent imaging has numerous advantages over incoherent imaging, but at a cost of requiring coherent laser illumination.
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Progress in coherent diffraction imaging: ptychography and coherent modulation imaging
Infrared and Laser Engineering, 2019Coherent diffraction imaging(CDI) is a lensless computational imaging technique, which reconstructs the amplitude and phase of an object directly from diffraction intensity measurement by solving the phase problem using iterative algorithms. CDI can provide images at the diffraction limit resolution that is only determined by the wavelength of ...
张福才 Zhang Fucai +5 more
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