Accession Number : AD0865860
Title : Laser Non-Scanning Techniques Feasibility Study.
Descriptive Note : Final rept. 1 May 68-3 Mar 69,
Corporate Author : AMPEX CORP REDWOOD CITY CA
Personal Author(s) : Markevitch, Bob V. ; Heeckeren, Jacob van ; Olenick, Ralph
Report Date : FEB 1970
Pagination or Media Count : 131
Abstract : The purpose of the work carried out was proof of feasibility of recording 24,000,000 bits of digital information into a dedicated area of 0.25 inch x 4 inch near the top of a COSATI format microfiche by recording 667 holograms at 3600 bits each. The effort is centered around the concept of writing the information in holographic form rather than bit-by-bit. In this scheme, the digital information is grouped into 3,600 bit blocks which are then recorded as one of 667 such holograms into the dedicated space. Whereas the early effort depended on the use of a liquid cell modulator to store the information to be recorded, the final development of the digital modulator was based on the concept of voltage controlled liquid crystals. The digital information contained in the hologram was successfully read out. Readout of the resultant display was accomplished electronically by means of a Vidicon television camera. The advantages of holographic digital recording lie in its extremely high tolerance to physical damage, and the extremely low registration requirements upon playback. Damage resistance was amply demonstrated by the satisfactory reconstruction of the bit pattern from holograms that had been artificially damaged, by dust, grease, severe scratches and cuts and even entire erasure of more than half of the hologram surface by black ink. (Author)
Descriptors : *PHOTOGRAPHIC RECORDING SYSTEMS), *DATA STORAGE SYSTEMS), (*LASERS, (*MICROFICHE, (*DIGITAL RECORDING SYSTEMS, MICROFICHE), STEREOPHOTOGRAPHY, PHOTOGRAPHY, FEASIBILITY STUDIES, ELECTROOPTICS, VIDICONS, MODULATION.
Subject Categories : Lasers and Masers
Distribution Statement : APPROVED FOR PUBLIC RELEASE