Patent ID: 6898167

Claim:
A method for storing data on an optical disk, the disk being comprised of a material which a holographic grating can be created at plural locations within the disk wherein the holographic grating represents a stored data element, the method comprising the steps of: recording data elements by creating a holographic grating at selected ones of the plural locations within the disk; and reading data elements by detecting one of (i) a presence, or (ii) an absence of a holographic grating at the plural locations within the disk, wherein: (a) the material comprising the optical disk is further capable of having multiple holographic gratings created within each of the plural locations; (b) the recording step comprises creating multiple data elements at each one of the plural locations by one of (i) creating a holographic grating, or (ii) refraining from creating a holographic grating, each of the holographic gratings created via a beam of light generated by an electro-optical head, said beam of light having a different wavelength for each holographic grating created in a same one of the plural locations; and, (c) the reading step comprises reading multiple data elements at each one of the plural locations by detecting one of (i) a presence of a holographic grating, or (ii) an absence of the holographic grating, via a beam of light generated by the electro-optical head, said beam of light being sequentially varied in wavelength to correspond to a wavelength of light and sequence of wavelengths employed to record each one of the multiple data elements recorded.