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Annual Meeting Optical Society of America, 1988
Ordinary holograms are made by interference experiments, digital holograms by computer and plotter. The object does not have to exist physically. Most advantages of digital holograms derive from that fact. Fundamentals and some applications are reviewed: AO display; image processing; and testing.
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Ordinary holograms are made by interference experiments, digital holograms by computer and plotter. The object does not have to exist physically. Most advantages of digital holograms derive from that fact. Fundamentals and some applications are reviewed: AO display; image processing; and testing.
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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
Daniel, Claus +2 more
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Digital holography-based steganography
Optics Letters, 2010A steganographic method offering a high hiding capacity is presented in which the techniques of digital holography are used to distribute information from a small secret image across the larger pixel field of a cover image. An iterative algorithm is used to design a phase-only or complex hologram from a padded version of the secret image, quantizing ...
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Digital diffusers for optical holography
Optics Letters, 1991In optical Fourier holography, diffuse illumination is used to achieve an almost linear recording of the spatial frequencies of the object on film. To this end, usually a ground glass is placed next to the object. However, then a speckle pattern occurs in the reconstruction. In digital holography, diffusers can be designed that do not introduce speckle.
R, Bräuer +3 more
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Optimum quantization in digital holography
Applied Optics, 1978Finite plotter resolution introduces quantization into the representation of digital holograms. By utilizing the statistical properties of the Fourier transform of random phase images, optimum quantization schemes are derived and tabulated for the representation of these transforms.
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