Remote Real-Time Reconstruction of Holograms Using the Lumatron

A system capable of generating holograms at one place and simultaneously reconstructing them at another has been developed and demonstrated. A 1.2-cm(2) Fourier transform hologram is converted, by means of the photoconductor and scanning electron beam in a vidicon, into a video signal. Then via an 8.5-MHz bandwidth video channel this signal is fed to a Lumatron at another location. In the Lumatron a second electron beam synchronized to the one in the vidicon causes a diffracting structure, depth-modulated as per the amplitude modulation of the hologram signal, to be formed in a thin layer of reusable thermoplastic. A laser beam passing coaxially through the Lumatron and the thermoplastic during this process generates the reconstructed twin images of the original object.