Abstract

In a variety of applications computers acquire or generate the data which represent 3-D objects, e.g., tomography and computer graphics. holography could be an adequate display technique, and it is possible to generate holograms using computers. The most important step to be considered is calculation of the complex amplitude. Suitable techniques and special schemes are reviewed. Several techniques simulate the wave propagation from the 3-D object to the hologram plane: (a) analytic solutions of the wave equation, especially conical waves which achieve segments of line foci; (b) diffracted fields are determined by a Fresnel transformation, and tilted input planes require an additional coordinate transformation. The boundary conditions of an optical recording step do not apply to a generation by computer, but there remain the boundary conditions of the optical reconstruction step. Synthetic techniques are possible: (c) the complex amplitude distributions are modified for each plane in-depth individually to reduce the computing time some orders of magnitude; (d) the assumption of a slitlike exit pupil leads to a separation of the calculation in 1-D Fresnel transforms and makes it possible to reconstruct in white light.

© 1988 Optical Society of America