Dye precursor molecules chemically reactive with the light-altered form of light-sensitive molecules to form stable fluorescent dye, particularly for optical memories including two-photon three-dimensional optical memories

A photochemical method directing to creating stable molecules having any of emissions, absorption, coloration and index of refraction different from precursor molecules from which the stable molecules are formed, the method comprising:

• placing within a matrix
• dye precursor molecules reactive with at least one of acids, bases, ions or radicals to produce dye molecules having differing spectroscopic properties than do the dye precursor molecules, along with
• light-sensitive molecules that, when exposed to light, undergo photochemical reaction so as to form at least one of the acids, bases, ions or radicals with which the dye precursor molecules are reactive;
• illuminating with radiation the matrix and the light-sensitive molecules contained therein so as to photo generate from the light-sensitive molecules at least one of the acids, bases, ions or radicals with which the dye precursor molecules are reactive;
• and
• permitting the photo generated acids, bases, ions or radicals to react with the dye precursor molecules to form the dye molecules.

An admixture, suitable for use in two-photon optical memories, consisting essentially of:

• dye precursor molecules reactive with at least one of acids, bases, ions or radicals to produce dye molecules having differing spectroscopic properties than do the dye precursor molecules;
• and
• light-sensitive molecules
• that, when exposed to first photons of a first frequency, is elevated to a first singlet or triplet state in which it is non-reactive,
• but that further, upon quantum-mechanically-simultaneous absorption of second photons of a second frequency, become excited to a higher singlet or triplet state, as the case may be,
• from which higher state the light sensitive molecules then, and only then, undergo photochemical reaction so as to form at least one of the acids, bases, ions or radicals with which the dye precursor molecules are reactive;
• wherein the dye precursor molecules are reactive with at least one acid, base, ion or radical, photo generated in the presence of both first and second photons from the light-sensitive molecules, to form the dye molecules.

An optical memory comprising:

• a multiplicity of addressable domains each containing
• dye precursor molecules reactive with at least one of an acid, a base, an ion or a radical to produce dye molecules having differing spectroscopic properties than do the dye precursor molecules;
• in proximity to
• light-sensitive molecules that, when exposed to light, undergo photochemical reaction so as to form at least one of the acid, base, ion or radical with which the dye precursor molecules are reactive;
• radiation write means for selectively radiatively illuminating the multiplicity of addressable domains so that the dye precursor molecules of selected domains are reactive with at least one acid, base, ion or radical photo generated from the light-sensitive molecules of these selected domains so to form dye molecules within these selected, written, domains, while other, un-selected, un-written, domains remain unchanged;
• and
• radiation read means for illuminating over time all the multiplicity of addressable domains both selectively written and not so that dye molecules within the written domains do respond in any of fluorescence, absorption or index of refraction in a detectably different manner than do the dye precursor molecules that are still within the un-written domains;
• wherein the optical memory may be radiatively optically read of information previously radiatively written therein.