HoloTape®: A Low-Cost Prerecorded Television System Using Holographic Storage

The RCA HoloTape system is designed to prerecord monochrome and color TV programs on a special tape for later playback over conventional TV receivers and monitors. For color TV programs, the luminance and chrominance signals are converted to a pair of images that are recorded on photoresist-coated plastic tape in the form of “Fraunhofer” holograms. Ways of increasing hologram redundancy and thus decreasing image noise are examined. The process of replicating Holo-Tapes involves recording holograms in a photoresist layer, electroforming a nickel master and thermomechanically embossing the holographic information onto a thermoplastic film. High-quality stereo sound is recorded in a groove near the tape edge using phonograph-record technology. The HoloTape system is naturally compatible with the NTSC, PAL and SECAM color systems. The player consists of only the tape and simple transport, a low-power helium-neon laser, a sound pickup and a TV camera.