Fourier, Fresnel and Image CGHs of three-dimensional objects observed from many different projections

We describe new techniques of synthesizing three types of computer-generated hologram (CGH); Fourier, Fresnel and image CGHs. These holograms, aimed to reconstruct three-dimensional (3-D) objects, are synthesized by means of a unique algorithm of fusing multiple perspective views of the observed scene. The hologram is initially generated in the computer as a Fourier hologram. Then, it can be converted to either Fresnel or image holograms by computing the desired wave propagation and the interference process. By illuminating the ready-to-use CGHs with a collimated plane wave, a 3-D image of the objects is reconstructed. Diffraction efficiency enhancement of the above algorithm by superimposing a random phase on the object during the CGH formation is also presented. Computer simulation and experimental results of the constructed 3-D objects demonstrate the suggested technique.