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The early mark-I electro-holography system provided either monochromatic or full-color display of holographic images by trading off vertical spatial resolution for three separate color channels.





The Mark-I Holographic Video Display is capable of rendering full-color
25x25x25mm images with a 15° view-zone at rates over 20 frames per
second. The holographic image is generated using a three-channel
tellurium-dioxide Acousto-Optic Modulator (AOM). A holographic fringe
pattern is sent through each channel of the AOM to modulate red (HeNe),
green (double-YAG) and blue (HeCd) light. The three resulting wavefronts
are combined using a Holographic Optical Element (HOE), to produce one
horizontal line of the horizontal-parallax-only image. To provide sufficient
resolution for the holographic diffraction pattern, each horizontal line is 32K
samples per color. Since the holographic fringe pattern in the AOM is
moving, a horizontal scanning mirror (18-sided spinning polygon) is used
to scan out the horizontal line and make the image appear stationary. A
vertical scanning mirror is used to produce 64 lines (at video resolution)
in a raster scan fashion.

Each frame of the holographic image is 6-MBytes and needs to provided
by a frame buffer as a 32K-sample horizontal by 64-line vertical signal
simultaneously for red, green and blue. We are currently using a Silicon
Graphics Onyx with an RE2 to be able to produce these patterns in this
format at near video rates. The display can be run in two modes, either
displaying pre-computed images at over 20 frames per second, or in
interactive mode updating the image at over 2 frames per second. In
interactive mode, a user can manipulate the image using several dials,
and each new 6-MByte fringe pattern is computed on the fly. User
operations include choosing new 3D objects, scaling and rotating those
objects, and changing the lighting direction.


The design of the Mark-I monochromatic and full color display is detailed in the following papers:

P. St.-Hilaire, S.A. Benton, M. Lucente, and P.M. Hubel, "Color images with the MIT holographic video display," in: S.A. Benton, ed., SPIE Vol. 1667, Practical Holography VI (Feb., 1992), paper 1667-73, pp. 73-84.

Mary Lou Jepsen, "Holographic video: design and implementation of a display system", S.M. Thesis, Department of Architecture, Massachusetts Institute of Technology, 1989.

Joel S. Kollin, "Design and information considerations for holographic television", S.M. Thesis, Department of Architecture, Massachusetts Institute of Technology, 1988.

For information on computation and rendering of images on the Mark-I display, see:

John Underkoffler, "Towards Accurate Computation of Optically Reconstructed Holograms", S.M. Thesis, Program in Media Arts and Sciences, Massachusetts Institute of Technology, June 1991.

Mark Lucente and Tinsley Galyean, "Rendering Interactive Holographic Images" Proceedings of SIGGRAPH '95 (Los Angeles, CA, Aug. 6-11, 1995), pp. 387-394.

For additional references, see our publications page.