Article

Computer-generated holograms for three-dimensional surface objects with shade and texture

Department of Electrical Engineering and Computer Science, Kansai University, 3-3-35 Yamate-cho, Suita, Osaka 564-8680, Japan.
Applied Optics (Impact Factor: 1.69). 09/2005; 44(22):4607-14. DOI: 10.1364/AO.44.004607
Source: PubMed

ABSTRACT Digitally synthetic holograms of surface model objects are investigated for reconstructing three-dimensional objects with shade and texture. The objects in the proposed techniques are composed of planar surfaces, and a property function defined for each surface provides shape and texture. The field emitted from each surface is independently calculated by a method based on rotational transformation of the property function by use of a fast Fourier transform (FFT) and totaled on the hologram. This technique has led to a reduction in computational cost: FFT operation is required only once for calculating a surface. In addition, another technique based on a theoretical model of the brightness of the reconstructed surfaces enables us to shade the surface of a reconstructed object as designed. Optical reconstructions of holograms synthesized by the proposed techniques are demonstrated.

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