Compositions and methods for storing holographic data
View Patent ↗The present invention provides a method for storing holographic data comprising providing a holographic storage medium comprising an optically transparent substrate including a photochemically active dye having at least two nitrone groups; and irradiating the optically transparent substrate with a holographic interference pattern, wherein the pattern has a first wavelength and an intensity both sufficient to convert, within a volume element of the substrate, at least some of the photochemically active dye into a photo-product, and producing within the irradiated volume element concentration variations of the photo-product corresponding to the holographic interference pattern, thereby producing a first optically readable datum corresponding to the volume element.
1. A method for storing holographic data comprising:
(A) providing a holographic storage medium comprising an optically transparent substrate, said optically transparent substrate comprising a photochemically active dye having structure (V)
wherein R 1 is independently at each occurrence a C 1 -C 20 aliphatic radical, a C 3 -C 20 cycloaliphatic radical, or a C 2 -C 30 aromatic radical; R 2 , R 3 , and R 4 are independently at each occurrence hydrogen, deuterium, a C 1 -C 20 aliphatic radical, a C 3 -C 20 cycloaliphatic radical, or a C 2 -C 30 aromatic radical; “a” is an integer from 2 to 4; and has a decompositon temperature greater than 250° C.; and
(B) irradiating the optically transparent substrate with a holographic interference pattern, wherein the pattern has a first wavelength and an intensity both sufficient to convert, within a volume element of the substrate, at least some of the photochemically active dye into a photo-product, and producing within the irradiated volume element concentration variations of the photo-product corresponding to the holographic interference pattern, thereby producing an optically readable datum corresponding to the volume element.
2. The method of claim 1 , wherein the optically transparent substrate comprises a thermoplastic polymer, a thermosetting polymer, or a combination comprising at least one of the foregoing polymers.
3. The method of claim 1 , wherein the optically transparent substrate comprises a polycarbonate.
4. The method of claim 1 , wherein the optically transparent substrate has a thickness of greater than about 100 micrometers.
5. The method of claim 1 , wherein the photochemically active dye is
wherein R 3 and R 4 are independently halogen, hydrogen, deuterium, a C 1 -C 20 aliphatic radical, a C 3 -C 20 cycloaliphatic radical, or a C 2 -C 30 aromatic radical; and R 5 is independently at each occurrence a C 1 -C 20 aliphatic radical, a C 3 -C 20 cycloaliphatic radical, or a C 2 -C 30 aromatic radical.
6. The method of claim 1 , wherein the optically transparent substrate comprises the photochemically active dye in an amount from about 0.1 weight percent to about 20 weight percent.
7. The method of claim 1 , wherein the photo-product comprises an oxaziridine, a rearrangement product of an oxaziridine, or a combination thereof.
8. he method of claim 1 , further comprising stabilizing the holographic interference pattern.
9. A method for storing holographic data comprising:
(A) providing a holographic storage medium comprising an optically transparent substrate, said optically transparent substrate comprising a photochemically active dye having structure (V)
wherein R 1 is independently at each occurrence a C 1 -C 20 aliphatic radical, a C 3 - C 20 cycloaliphatic radical, or a C 2 -C 30 aromatic radical; R 2 , R 3 , and R 4 are independently at each occurrence hydrogen, deuterium, a C 1 -C 20 aliphatic radical, a C 3 -C 20 cycloaliphatic radical, or a C 2 -C 30 aromatic radical; “a” is an integer from 2 to 4; and has a decompositon temperature greater than 250° C.; and
(B) irradiating the optically transparent substrate with a holographic interference pattern, wherein the pattern has a first wavelength in a range from about 450 nanometers to about 550 nanometers and an intensity both sufficient to convert, within a volume element of the substrate, at least some of the photochemically active dye into a photo-product, and producing within the irradiated volume element concentration variations of the photo-product corresponding to the holographic interference pattern, thereby producing an optically readable datum corresponding to the volume element.
10. The method of claim 9 , wherein the optically transparent substrate comprises a thermoplastic polymer, a thermosetting polymer, or a combination comprising at least one of the foregoing polymers.
11. The method of claim 9 , wherein the optically transparent substrate has a thickness of greater than about 100 micrometers.
12. The method of claim 9 , wherein the optically transparent substrate comprises the photochemically active dye in an amount from about 0.1 weight percent to about 20 weight percent.
13. The holographic storage medium of claim 9 , further comprising stabilizing the holographic interference pattern.
14. A method for storing holographic data comprising:
(A) providing a holographic storage medium comprising an optically transparent substrate, said optically transparent substrate comprising a photochemically active dye having structure (V)
wherein R 1 is independently at each occurrence a C 1 -C 20 aliphatic radical, a C 3 -C 20 cycloaliphatic radical, or a C 2 -C 30 aromatic radical; R 2 R 3 , and R 4 are is independently at each occurrence hydrogen, deuterium, a C 1 -C 20 aliphatic radical, a C 3 -C 20 cycloaliphatic radical, or a C 2 -C 30 aromatic radical; and “a” is an integer from 2 to 4, and has a decompositon temperature greater than 250° C.;
wherein the dye is present in an amount from about 0.1 weight percent to about 20 weight percent; and
(B) irradiating the optically transparent substrate with a holographic interference pattern, wherein the pattern has a first wavelength wavelength in a range from about 400 nanometers to about 650 nanometers and an intensity both sufficient to convert, within a volume element of the substrate, at least some of the photochemically active dye into a photo-product, and producing within the irradiated volume element concentration variations of the photo-product corresponding to the holographic interference pattern, thereby producing an optically readable datum corresponding to the volume element, and wherein the first wavelength is about 500 nm.
15. A holographic storage medium comprising (i) at least one optically transparent plastic material, and (ii) at least one photochemically active dye having structure (V)
wherein R 1 is independently at each occurrence a C 1 -C 20 aliphatic radical, a C 3 -C 20 cycloaliphatic radical, or a C 2 -C 30 aromatic radical; R 2 , R 3 , and R 4 are independently at each occurrence hydrogen, deuterium, a C 1 -C 20 aliphatic radical, a C 3 -C 20 cycloaliphatic radical, or a C 2 -C 30 aromatic radical; “a” is an integer from 2 to 4; and has a decompositon temperature greater than 250° C.