This invention relates to a three-dimensional optical memory made from a fluorescent
photosensitive material, and a method and device for the storage and retrieval
of information on the three-dimensional optical memory. The fluorescent photosensitive
material can be glass and vitroceramic, both of which exhibit both fluorescent
and photosensitive properties. Both one-photon and two-photon processes can be
used for writing and reading the digital information on to the three-dimensional
optical memory, in conjunction with a confocal microscope. A high reading sensitivity
is obtained by using fluorescence during the reading cycle.