A method of enlarging an observation window from which the reconstruction from a Computer Generated Hologram (CGH) may be viewed, including reproducing a CGH, and shifting a location of an exit pupil or observation window of an optical system reproducing the CGH. A method of increasing a viewing angle from which the reconstruction from a Computer Generated Hologram (CGH) may be seen, including producing a plurality of instances of a CGH, projecting each one of the instances in a different direction so that a first exit pupil of a first instance is close to a second exit pupil of a second instance. An optical system including a plurality of exit pupils associated with a plurality of optical components, further including a light deflector for jittering a location of a first exit pupil so as to increase an overlap of the first exit pupil with a second exit pupil. Related apparatus and methods are also described.

The invention pertains in a first aspect to a multilayer film that includes a frangible holographic image layer and an adhesive layer adjacent to a side of the holographic image layer; and, an additional temporary support layer that is adjacent a side of the holographic image layer that is opposite the adhesive layer, and provides integrity to the multilayer film. The additional temporary support layer can be a polyester film that is removable from the multilayer film at 10 gram per inch peel strength; or, can be a heat-shrinkable film that is removable from the multilayer film with the application of heat. After application of the multilayer film to a substrate, the holographic image layer forms an exterior surface of the multilayer film. In a second aspect, the invention pertains to an authentication label of the multilayer film for attachment to a substrate, wherein a side of the adhesive layer that is opposite the holographic image layer contacts the substrate, and the holographic image layer forms an exterior surface of the label.

A method for despeckling the image reproduced by a Computer Generated Hologram (CGH) including reproducing a CGH, and jittering a location of an exit pupil of an optical system through which the CGH is imaged, relative to an observer's input pupil, so as to shift at least some speckles out of the exit pupil. A method for despeckling a Computer Generated Holographic image including computing a first modulation for a first holographic image, and computing a second modulation for a second holographic image of a same holographic image using an initial phase distribution used for calculating the first holographic image as an initial phase distribution used for calculating the second modulation. Related apparatus and methods are also described.

An object of the present invention is to provide a thin volume hologram sheet to be embedded sufficiently resistant to a mechanical stress such as a stress including a tensile stress, a shear stress and a compression stress at the time of processing even under a heating condition, a forgery prevention paper and a card using the same. The object is achieved by providing a volume hologram sheet to be embedded comprising a volume hologram layer, and a substrate disposed only on one side surface of the volume hologram layer using an adhesion means, wherein a peeling strength of the volume hologram layer and the substrate is 25 gf/25 mm or more.

In the specification and drawings, a collinear holographic storage medium is described and shown with a recording layer, wherein the lateral linear thermal expansion coefficient of the recording layer is substantially the same as the linear thermal expansion coefficient of the material of the recording layer.