two-layer holographic data storage media

Holodisks can be made by combining two different layers of polymer. One layer does not respond much with lasers, but gives structural support for the disk. The other layer does not have much internal support, but responds well with the laser and is connected to the structural layer. The use of two different strata enables the creation of holodisks that are both solid and photosensitive. Several types of substances have been tested as potential holotechnology storage media, including iron-enhanced lithium- niobate crystal and stoichiometric lithium niobate. Included in the alternative substances for holodisks, polycarbonate substances may be chemically changed when illuminated by a certain type of laser. Due to their initial high expense, holotechnology information disks are likely to be first used for high-resolution digital video broadcasting and movie distribution for digital theaters. Sub-page MIT Media Lab: HoloVideo covers further information.

In addition to rendering quicker access and more capacity, holotechnology technology pioneers novel means of data comparison and retrieval. Most present day information storage and extraction systems need exact specification of information placement in order to retrieve information and they process it in a linear sequence. In contrast, holotechnology technology enables exploring large quantities of information a whole page at once to contrast overall configurations and sameness of patterns. With holotechnology technology, the degree of similarity between a high-level search pattern and information pages throughout an optical volume can be quantified without discrete analysis of specific data elements. This is known as "Associative Retrieval." Associative retrieval is more compatible with lack of precision and fuzzy logic, and more closely related to human cognition, than traditional data storage and extraction systems. Also Virtual Display has related holotech developments.

Linked page Holographic Disks also has information that may be of interest.