Results 281 to 290 of about 219,223 (311)
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Binary Fraunhofer Holograms, Generated by Computer
Applied Optics, 1967When a hologram is desired from an object which does not exist physically but is known in mathematical terms, one can compute the hologram. An automatic plotter will make a drawing at a large scale which is then reduced photographically. Since the drawing can contain only black and white areas, we have developed a theory for binary holograms.
A W, Lohmann, D P, Paris
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Image encryption based on computer generated hologram and Rossler chaotic system
Optical and quantum electronics, 2021Ibrahim A. Hamadi, R. K. Jamal, S. Mousa
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Computer-generated holograms with error compensation
Applied Optics, 1988We analyze computer-generated holograms (CGH) of Lohmann types I and III and discuss their overall errors employing the following modifications, listed in order of increasing importance: phase-only correction (Ptype), virtual increase of the cell number, optimized use of the available plotting area, expansion of the amplitude dynamic range (D-type ...
W, Freude +3 more
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Computer-generated hologram for optical testing: a review
Optical Engineering + Applications, 2021Chunyu Zhao
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Rotational control of computer generated holograms
Optics Letters, 2017We develop a basis for three-dimensional rotation of arbitrary light fields created by computer generated holograms. By adding an extra phase function into the kinoform, any light field or holographic image can be tilted in the focal plane with minimized distortion.
Preece, Daryl +1 more
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Polarizing computer-generated holograms
Optical Engineering, 1993Polarizing computer-generated holograms (PCGH) may be useful combining different optical functions such as polarizing, imaging, beam shaping, and beamsplitting in one element. We propose the fabrication of PCGHs based on microstructuring of polarizing or birefringent materials.
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High-efficiency hybrid computer-generated holograms
Applied Optics, 1982A hybrid hologram is constructed which combines the flexibility of a computer-generated hologram (CGH) with the high-diffraction efficiency of volume phase holograms. The new hologram is constructed by using a spatially filtered wave front from a conventional 246- x 256-cell CGH as the object wave for the recording of a volume hologram. Theoretical and
H, Bartelt, S K, Case
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Optical image encryption and authentication using phase-only computer-generated hologram
, 2021Wenqi Wang +3 more
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Computer-generated hologram statistics
SPIE Proceedings, 2010The statistical distributions of phase values in computer-generated holograms produced with iterative algorithms are studied. Useful relationships between the parameter values applied in the iterative technique used for their generation and measured performance are provided.
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Single-substrate birefringent computer-generated holograms
Optics Letters, 1996A polarization-selective computer-generated hologram fabricated upon a single substrate of birefringent YVO(4) crystal is demonstrated. Rigorous couple-wave analysis was used to model the element. The experimentally measured first diffraction order showed a close-to-theoretically predicted diffraction efficiency of 39%.
F, Xu, R C, Tyan, Y, Fainman, J E, Ford
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