In late 1995 a joint university, industry and government consortium initiated the Holographic Data Storage System (HDSS) programme, with the initial goals of developing several key components for the system, including a high-capacity, high-bandwidth
spatial light modulator used for data input; optimised sensor arrays for data output; and a high-power red-light,
semiconductor laser. At the same time, the HDSS researchers were to explore issues relating to the optical systems architecture (such as
multiplexing schemes and access modes), data encoding and decoding methods,
signal processing techniques, and the requirements of target applications. Into the programme's final year, progress has been such that consortium member -
IBM Research Division - believes that
holograms could hold the key to high-capacity data storage in the next millennium. Large amounts of data can be stored holographically because lasers are able to store pages of electronic patterns within special optical materials as opposed to just on the surface. In traditional holography, each viewing angle gives a different aspect of the same object. With holographic storage, however, a different 'page' of information is accessed.
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HOLOGRAPHIC DATA STORAGE SYSTEM. HDSS