A liquid crystal laminate includes a substrate including a first diffraction surface and a second base material surface and having optical transparency, a metal layer located on a part of the first diffraction layer, an adhesion layer located on a part of the second base material layer and made of a photocured resin, and liquid crystal layer located on a surface of the adhesion layer at a side opposite to the contact surface of the substrate.

A holographic antenna for recording a comprehensive interference pattern beyond the mere minimum and maximum values and reconstructing waveform of a target antenna includes a feed antenna and a holographic structure. The holographic structure includes a substrate and a plurality of spaced metal strips disposed on the substrate. Heights of the metal strips are negatively correlated with intensities of the interference pattern. A method for fabricating such a holographic antenna is also provided.

A method for producing a hologram (1), (1) for security elements (1a) and/or security documents (1b). One or more virtual hologram planes (10) are arranged in front of and/or behind one or more virtual models (20) and/or one or more virtual hologram planes (10) are arranged such that they intersect one or more virtual models (20). One or more virtual light sources (30) are arranged on one or more partial regions of the surface (21) of one or more of the virtual models (20). One or more virtual electromagnetic fields (40) are calculated starting from at least one of the virtual light sources (30) in one or more zones (11) of the one or more virtual hologram planes (10). In the one or more zones (11), in each case, a virtual total electromagnetic field (41) is calculated on the basis of the sum of two or more, of the virtual electromagnetic fields (40) in the respective zone (11). One or more phase images (50) are calculated from the virtual total electromagnetic fields (41) in the one or more zones (11). A height profile (60) of the hologram (1) is calculated from the one or more phase images (50) and the height profile (60) of the hologram (1) is incorporated into a substrate (2) to provide the hologram (1).

A device in holographic imaging comprises: at least two light sources, wherein each of the at least two light sources is arranged to output light of a unique wavelength; and at least one holographic optical element, wherein the at least two light sources and the at least one holographic optical element are arranged in relation to each other such that light from the at least two light sources incident on the at least one holographic optical element interacts with the at least one holographic optical element to form wavefronts of similar shape for light from the different light sources.

A holographic security or identification device (10) comprises an object, or a flexible substrate (12) configured to be conformable to a desired, curved shape; and a plurality of structures (14) formed on or in the object to have a desired curved configuration, or formed in or associated with the substrate and arranged to adopt a desired curved configuration when the substrate is conformed to a desired shape, wherein the plurality of structures (14) are configured to receive light (20) of a selected at least one wavelength or range of wavelengths and to produce, using the received light, a desired holographic image (22) for security or identification purposes when in the desired configuration.

The present disclosure relates to a hologram medium comprising: a polymer substrate including a polymer resin in which a silane-based functional group is located in a main chain or a branched chain, wherein a fine pattern is formed on at least one surface of the polymer substrate, and an optical element.

A hologram that includes a formation layer and a reflection layer that are laminated. The formation layer has an optical phase modulation structure on a first interface in contact with the reflection layer. When reference light emitted from a point light source enters through a second interface different from the first interface of the formation layer, the entirety or part of an image to be reconstructed by the optical phase modulation structure is reconstructed as spatial information on the point light source side relative to the second interface.

A display including a plurality of pixels each including a plurality of first subpixels and a plurality of second subpixels. In pixel, when illumination light is applied to the first subpixels from a normal direction, no diffracted light emerges from the plurality of first subpixels, or first diffracted light emerges from the plurality of first subpixels in a first angular range. When illumination light is applied to the second subpixels from the normal direction, no diffracted light emerges from the plurality of second subpixels, or second diffracted light having a wavelength equal to that of the first diffracted light emerges from the plurality of second subpixels in a second angular range wider than the first angular range, at an intensity lower than that of the first diffracted light; with the pixels configured to display a continuously changing image using the first diffracted light and the second diffracted light.

Some embodiments are directed to a system for measuring vibrations of a surface of a mechanical part, by digital holography. The system includes a source of radiation emitting in a predetermined range of frequencies, a first separator element configured to define a first incident ray and a reference ray, a module for shaping a second incident ray from the first incident ray, and an optical element configured to make the reference ray and a radiation produced by a reflection of the incident ray on the surface of the mechanical part interfere. The module for shaping the second incident ray includes diffracting optical elements having a diffraction structure to diffract the incident radiation. The structure is from a polymer, sol-gel or photoresin material resting against a glass substrate, the structure including elements etched in a plane parallel and/or orthogonal to the substrate, with dimensions from 100 nanometres to 100 micrometres.

There is provided a holographic security element including a substrate; and an array of nano-reflectors configured to form a pattern on the substrate and to generate a holographic image corresponding to the pattern at a predetermined distance from the substrate when irradiated with a predetermined light source. In particular, the array of nano-reflectors is configured to generate the holographic image at the predetermined distance to have a size that is larger than a size of the pattern. There is also provided a method of forming the holographic security element, and an article having one or more holographic security elements incorporated therein.