Patent ID: 7190649

Claim:
A method of reading information stored on a data storage medium comprising the steps of: (a) exciting a luminescent data storage medium with an optical source to thereby cause said luminescent data storage medium to emit a fluorescent light signal, wherein said luminescent data storage medium comprises Al 2 O 3 and wherein said optical source emits a read laser beam having a wavelength in the range of an absorption band of said luminescent data storage medium; and (b) measuring said laser induced fluorescence light signal from said luminescent data storage medium, to thereby read said information stored on said luminescent data storage medium, wherein said luminescent data storage medium comprises: a base material comprising Al 2 O 3 ; a first dopant comprising magnesium; and a second dopant comprising carbon, wherein said luminescent data storage medium includes a plurality of at least one type of oxygen vacancy defect, and wherein said luminescent data storage medium includes at least one color center having: an absorption bands in the regions of 250±5 nm, 335±5 nm and 620±10 nm, an emission in the region of 750±10 nm, and a 80±10 ns lifetime.