Process for the production of holograms

Claim 2

A PROCESS FOR THE PRODUCTION OF HOLOGRAMS WHEREIN THE PHASE HOLOGRAM OF AN IMAGE IS RECORDED, WHICH PROCESS COMPRISES EXPOSING A TRANSPARENT LIGHT-SENSITIVE REPRODUCTION MATERIAL, HAVING A LIGHT-SENSITIVE LAYER ON A TRANSPARENT SUPPORT, TO AN OBJECT BEAM AND A REFERENCE BEAM OF ACTINIC COHERENT LAIGHT WHEREBY A PHASE HOLOGRAM OF THE OBJECT IS PRODUCED, SAID LIGHT-SENSITIVE LAYER CONSISTING ESSENTIALLY OF A LIGHTSENSITIVE COMPOUND SELECTED FROM THE GROUP CONSISTING OF AN AROMATIC DIAZONIUM COMPOUND, A QUINONE DIAZIDE, AND AN AROMATIC NITRONE, WHEREUPON A VISIBLE IMAGE IS IMMEDIATELY RECONSTRUCTIBLE FROM THE OBTAINED HOLOGRAO BY PASSING NON-ACTINIC COHERENT LIGHT THROUGH THE EXPOSED TRANSPARENT LIGHTSENSITIVE REPRODUCTION MATERIAL, AND THEN RECORDING AT LEAST ONE FURTHER HOLOGRAM ONTO THE SAME MATERIAL BY MEANS OF ACTINIC LIGHT, EITHER ON THE SAME AREA BY VARYING THE SPATIAL FREQUENCY OR BY VARYING THE PLANE OF THE INCIDENT BEAMS, OR ON ANOTHER AREA OF SAID MATERIAL, WHEREUPON THE IMAGES FROM THE DIFFERENT HOLOGRAMS ARE INDEPENDENTLY RECONSTRUCTIBLE.

Claim 3

A process for the production of duplicate holograms wherein a phase hologram of an image is copied, which process comprises exposing a transparent light-sensitive reproduction material, having a light-sensitive layer on a transparent support, to actinic light in contact under a master hologram such that a duplicate hologram is produced, said light-sensitive layer consisting essentially of a light-sensitive compound selected from the group consisting of an aromatic diazonium compound, a quinone diazide, and an aromatic nitrone, whereupon a visible image is immediately reconstructible from the obtained duplicate hologram by passing non-actinic coherent light through the exposed transparent light-sensitive reproduction material, and then copying at least one further hologram onto the same material by means of actinic light, either on the same area by using a master hologram of a different spatial frequency or by turning the reproduction material with respect to the further hologram to be copied about an axis vertical to the plane of the hologram, or on another area of said material, whereupon the images from the different duplicate holograms are independently reconstructible.

Claim 4

A process for the production of duplicate holograms wherein a phase hologram of an image is copied, which process comprises exposing a transparent light-sensitive reproduction material, having a light-sensitive layer on a transparent support, to actinic light in contact under a master hologram such that a duplicate hologram is produced, said light-sensitive layer consisting essentially of a light-sensitive compound selected from the group consisting of an aromatic diazonium compound, a quinone diazide, and an aromatic nitrone, whereupon a visible image is immediately reconstructible from the obtained duplicate hologram by passing non-actinic coherent light through the exposed transparent light-sensitive reproduction material, and then copying at least one further hologram onto the same material by means of actinic light, either on the same area by using a master hologram of a different spatial frequency or by turning the reproduction material with respect to the further hologram to be copied about an axis vertical to the plane of the hologram, or on another area of said material, whereupon the images from the different duplicate holograms are independently reconstructible.

Claim 5

A process according to claim 1 in which the light-sensitive layer is embedded in the surface of the support.

Claim 6

A process according to claim 1 in which a recording material is used which contains an aromatic diazonium salt as the light-sensitive compound, and the recorded holograms are fixed after the last exposure to actinic light by alkaline development in the presence of a coupling component.

Claim 7

A process according to claim 1 in which a recording material is used which contains a quinone diazide as the light-sensitive compound, the hologram is swollen after exposure to actinic light by immersion in a developer solution, and the swollen hologram is dried.

Claim 8

A process according to claim 5 in which further holograms are added by exposure to actinic light, swelling, and drying.

Claim 9

A process according to claim 6 in which the recorded holograms are fixed by full exposure to actinic light.

Claim 10

A process according to claim 4 in which the light-sensitive compound is an aromatic diazonium salt having a secondary or tertiary amino group in the 4-position.

Claim 11

A process according to claim 5 in which the quinone diazide is a naphthoquinone-(1,2)-diazide-(2)-4- or 5-sulfonic acid ester.

Claim 12

A process according to claim 2 in which the light-sensitive layer is embedded in the surface of the support.

Claim 13

A process according to claim 2 in which a reproduction material is used which contains an aromatic diazonium salt as the light-sensitive compound, and the copied holograms are fixed After the last exposure to actinic light by alkaline development in the presence of a coupling component.

Claim 14

A process according to claim 2 in which a reproduction material is used which contains a quinone diazide as the light-sensitive compound, the hologram is swollen after exposure to actinic light by immersion in a developer solution, and the swollen hologram is dried.

Claim 15

A process according to claim 12 in which further holograms are added by exposure to actinic light, swelling, and drying.

Claim 16

A process according to claim 13 in which the copied holograms are fixed by full exposure to actinic light.

Claim 17

A process according to claim 11 in which the light-sensitive compound is an aromatic diazonium salt having a secondary or tertiary amino group in the 4-position.

Claim 18

A process according to claim 12 in which the quinone diazide is a naphthoquinone-(1,2)-diazide-(2)-4- or 5-sulfonic acid ester.