HOLOGRAPHIC DEVICE
A device comprising an authentication hologram recorded within a defined volume of a holographic recording medium, wherein the authentication hologram is configured to convey authentication information; wherein the authentication hologram comprises a plurality of related volumetric holograms recorded within the defined volume; and wherein the holographic recording medium comprises an optically transparent plastic material and a photochemically active dye. In one embodiment, all the holograms are identical. In one embodiment, the holograms are different.
1 . A device comprising:
an authentication hologram recorded within a defined volume of a holographic recording medium;
wherein the authentication hologram is configured to convey authentication information;
wherein the authentication hologram comprises a plurality of related volumetric holograms recorded within the defined volume; and
wherein the holographic recording medium comprises an optically transparent plastic material and a photochemically active dye.
2 . The device according to claim 1 , wherein the plurality of related volumetric holograms are substantially identical.
3 . The device according to claim 2 , wherein the authentication hologram is viewed by a hologram reader from different angles.
4 . The device according to claim 2 , wherein the authentication hologram is viewed by a human eye from different angles.
5 . The device according to claim 1 , wherein at least one hologram of the plurality of related volumetric holograms is optically encoded.
6 . The device according to claim 5 , wherein the authentication hologram is viewed by a hologram reader from different angles.
7 . The device according to claim 5 , wherein the authentication hologram is viewed by a human eye from different angles.
8 . The device according to claim 1 , wherein the authentication hologram appears as an animated sequence of images to a stationary observer.
9 . The device according to claim 8 , wherein the authentication hologram is viewed by a hologram reader from different angles.
10 . The device according to claim 8 , wherein the authentication hologram is viewed by a human eye from different angles.
11 . The device according to claim 1 , wherein the holographic recording medium in which the authentication hologram is recorded has a thickness in a range of about 5 micrometers to about 1200 micrometers.
12 . The device according to claim 1 , wherein the authentication hologram is recorded in a thin layer of the holographic recording medium.
13 . The device according to claim 12 , wherein the authentication hologram is viewed by a hologram reader from different angles.
14 . The device according to claim 12 , wherein the authentication hologram is viewed by a human eye from different angles.
15 . The device according to claim 12 , wherein the holographic recording medium in the device has a thickness in a range of about 5 micrometers to about 600 micrometers; wherein the authentication hologram is recorded throughout the thickness of the holographic recording medium.
16 . The device according to claim 1 , wherein the authentication hologram is artificially truncated.
17 . The device according to claim 16 , wherein the authentication hologram is viewed by a hologram reader from different angles.
18 . The device according to claim 16 , wherein the authentication hologram is viewed by a human eye from different angles.
19 . The device according to claim 16 , wherein the holographic recording medium in the device has a thickness, and a part of the thickness in which the authentication hologram is artificially truncated is in a range of about 5 micrometers to about 600 micrometers.
20 . The device according to claim 1 , wherein the device comprises a credit card, an identification card, hotel room key, an access key, a passport, a bill of currency, an authentication tag, a shipping manifest, a bill of lading, or an electronic information storage device.
21 . A method comprising,
providing a device comprising an authentication hologram recorded within a defined volume of a holographic recording medium,
wherein the authentication hologram is configured to convey authentication information;
wherein the authentication hologram comprises a plurality of related volumetric holograms recorded within the defined volume; and
wherein the holographic recording medium comprises an optically transparent plastic material and a photochemically active dye.
22 . The method according to claim 21 , wherein the plurality of related volumetric holograms are substantially identical.
23 . The method according to claim 22 , wherein the authentication hologram is recorded within one or more volume elements of a holographic recording medium;
wherein the related volumetric holograms are recorded a plurality of times at different angles in the same volume element of the medium; and
wherein each time of the plurality of times the related volumetric holograms are recorded one on top of another in the same volume element of the holographic recording medium.
24 . The method according to claim 21 , wherein the authentication hologram is artificially truncated.
25 . The method according to claim 24 , wherein the authentication hologram is artificially truncated by recording a hologram using light having a limited coherence length.
26 . The method according to claim 25 , wherein the authentication hologram is artificially truncated by limiting interaction region of the incident light with the holographic recording medium by limiting focus region of the signal beam and the reference beam.
27 . The method according to claim 21 , wherein the authentication hologram appears as an animated sequence of images to a stationary observer.
28 . The method according to claim 27 , wherein the authentication hologram is recorded within one or more volume elements of a holographic recording medium in a manner such that the information recorded one on top of another in the same volume element of the medium is modulated to have a relationship.
29 . The method according to claim 21 , wherein the frequency spectrum of the hologram is low enough to be not distorted by the reading wavelength; and wherein the reading wavelength is substantially different from the recording wavelength.
30 . The method according to claim 21 , wherein at least one hologram of the plurality of related volumetric holograms is optically encoded.
31 . A device comprising:
an authentication hologram recorded within a defined volume of a holographic recording medium;
wherein the authentication hologram is configured to convey authentication information;
wherein the authentication hologram comprises a plurality of substantially identical volumetric holograms recorded within the defined volume;
wherein the authentication hologram appears substantially identical when the device is viewed by a hologram reader from different angles; and
wherein the holographic recording medium comprises an optically transparent plastic material and a photochemically active dye.
32 . A device comprising:
an authentication hologram recorded within a defined volume of a holographic recording medium;
wherein the authentication hologram is configured to convey authentication information;
wherein the authentication hologram comprises a plurality of related volumetric holograms recorded within the defined volume;
wherein the authentication hologram appears as an animated sequence of images to a stationary observer; and
wherein the holographic recording medium comprises an optically transparent plastic material and a photochemically active dye.