Results 211 to 220 of about 51,169 (250)
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Unconventional digital holography
Digital Holography and Three-Dimensional Imaging, 2013Traditionally, holography requires coherent-light for object illumination and a reference beam for recording its 3-D information as a hologram. We explore the unconventional techniques for digital holography that avoid coherent-light and reference.
Wolfgang Osten +2 more
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Digital in-line holography of microspheres
Applied Optics, 2002We have used digital in-line holography (DIH) with numerical reconstruction to image micrometer-sized latex spheres as well as ferrimagnetic beads suspended in gelatin. We have examined in detail theoretically and experimentally the conditions necessary to achieve submicrometer resolution of holographic reconstructions.
Manfred H. Jericho +3 more
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Digital Hyperspectral Holography
Optoelectronics, Instrumentation and Data Processing, 2020A method and an optical scheme for recording digital hyperspectral holograms in the light of an incoherent source are considered. The optical scheme includes an interferometer with a scanning mirror for generating reference waves. The set of complex amplitudes of the object field is calculated by Fourier transform of the interferograms in each pixel of
S. G. Kalenkov, G. S. Kalenkov
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Time-averaged digital holography
Optics Letters, 2003We demonstrate that it is possible to study the modal structures of a vibrating object with digitally recorded holograms by use of the time-averaging principle. We investigate the numerical reconstruction from a theoretical point of view, and we show that the numerically reconstructed object from a digital hologram is modulated by the zeroth-order ...
Denis Mounier +3 more
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Multiwavelength Digital Holography
2015Another application of HI is the generation of a fringe pattern corresponding to contours of constant elevation with respect to a reference plane (see Fig. 7.1). Such contour fringes can be used to determine the shape of a 3D object. Holographic contour interferograms can be generated by the two-illumination-point method (discussed in Section 5.2 ...
Logan Williams +2 more
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Diffusers in digital holography
Journal of the Optical Society of America A, 1991In Fourier and Fresnel holography diffuse illumination is used to smooth the power spectrum of the object wave. A speckle pattern will then disturb the diffraction pattern. We present methods to calculate appropriate diffusers in digital holography that do not introduce speckle.
Frank Wyrowski +2 more
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Coherence requirement in digital holography
Applied Optics, 2012In this paper the coherence requirement for different holographic setups (Fresnel hologram, Fourier hologram, and image-plane hologram) is compared. This analysis is based on the investigation of the recorded interference pattern from the superposition of reference wave and object wave in in-line and off-axis mode. The outcome of this investigation can
John M. Rodenburg +2 more
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SPIE Proceedings, 2011
We have created a programming tool which uses image data provided by webcam connected to personal computer and gives user an ability to see the future digital hologram preview on his computer screen, before sending video data to holographic printing companies.
Andrej Nikolskij +2 more
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We have created a programming tool which uses image data provided by webcam connected to personal computer and gives user an ability to see the future digital hologram preview on his computer screen, before sending video data to holographic printing companies.
Andrej Nikolskij +2 more
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SPIE Proceedings, 2005
The Modulation Transfer Function (MTF) in digital holography is discussed. Theoretical derivation of its form is given. Specific properties of the MTF for different parameters of hologram detector are presented.
Marek J. Matczak, Leszek Pyziak
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The Modulation Transfer Function (MTF) in digital holography is discussed. Theoretical derivation of its form is given. Specific properties of the MTF for different parameters of hologram detector are presented.
Marek J. Matczak, Leszek Pyziak
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Digital Holography for Security Applications [PDF]
, 2012 A survey of Digital Holography (DH) and its employment in different application fields is provided. This paper reviews the main principles of the DH focusing on the optical techniques for security purposes. Recording and processing of three dimensional data, secured storage data, the use of Multimedia Sensor Network (MSN) for encrypted data ...
Samuela Persia +3 more
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