A display body includes a base material having a first region, a second region, and a third region. In the display body, the first region is formed with a code or an image of identification information, and the second region is formed with a hidden code containing information obtained by encoding at least a part of the identification information. An encrypted ciphertext is recorded in the third region, and the ciphertext is generated from at least one of the code of the identification information and the hidden code.

An anti-microbial packaging includes an innermost decontamination layer defining an inside and exposed surface of the packaging against which items in the packaging would contact. A fiber substrate layer is fixed to the innermost decontamination layer which itself is a metal or a metallic-alloy layer.

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.

A decoration element including a color developing layer including a light reflective layer, a light absorbing layer provided on the light reflective layer, and a convex portion or concave portion having an asymmetric-structured cross-section; an electrochromic device provided on any one surface of the color developing layer; and an in-mold label layer provided on the other surface of the color developing layer.

A display including a relief structure forming layer having a major surface with a relief type diffractive structure that displays a three-dimensional object as a diffraction image; and a reflective layer at least partially covering a region of the major surface where the diffractive structure is provided. A portion of the diffractive structure in a first region includes first and second linear parts forming a first lattice, and first parts arranged in respective gaps of the first lattice. The first and second linear parts each having a solid line shape form a first pattern. A portion of the diffractive structure in a second region includes third and fourth linear parts alternately arranged in the width direction thereof. The third linear parts each having a dashed line shape and the fourth linear parts each having a dashed or dotted line shape form a second pattern.

A volume holographic film (such as a photopolymer) that is pre-recorded with patterns subsequently is used to encode LED or low-power laser light reflections from an eye into a binary pattern that can be read at very high speeds by a relatively simple complementary metal-oxide-semiconductor (CMOS) sensor that may be similar to a high framerate, low resolution mouse sensor. The low-resolution mono images from the film are translated into eye poses using, for instance, a look up table that correlates binary patterns to X, Y positions or using a pre-trained convolutional neural network to robustly interpret many variations of the binary patterns for conversion to X, Y positions.

Systems, devices, and methods for aperture-free hologram recording are described. The apertures typically used for hologram recording create unwanted secondary holograms by diffracting light. Aperture-free hologram recording eliminates these unwanted secondary holograms. Aperture-free hologram recording includes applying a mask to the holographic recording medium. The mask controls the size of the recorded hologram like an aperture but does not create unwanted secondary holograms. Hologram fringes are only present in the desired recording area and a thin boundary region. The mask may be present during recording, or the mask may be used to pre-bleach the holographic recording medium. Pre-bleaching the holographic recording medium renders a portion of the holographic recording medium insensitive to light, the hologram is recorded in the light-sensitive portions of the holographic recording medium.

Systems, devices, and methods for aperture-free hologram recording are described. The apertures typically used for hologram recording create unwanted secondary holograms by diffracting light. Aperture-free hologram recording eliminates these unwanted secondary holograms. Aperture-free hologram recording includes applying a mask to the holographic recording medium. The mask controls the size of the recorded hologram like an aperture but does not create unwanted secondary holograms. Hologram fringes are only present in the desired recording area and a thin boundary region. The mask may be present during recording, or the mask may be used to pre-bleach the holographic recording medium. Pre-bleaching the holographic recording medium renders a portion of the holographic recording medium insensitive to light, the hologram is recorded in the light-sensitive portions of the holographic recording medium.

The invention relates to a method for producing a holographic optical element by providing a recording stack comprising at least one recording element laminated on at least one supporting element, irradiating at least a part of the recording stack with at least one recording beam in an irradiating step, wherein during the irradiating step, the recording stack bends, providing a bending deviation threshold for the recording stack, and adjusting at least one first process parameter such that an expected maximum bending deviation of the recording stack does not exceed the bending deviation threshold, wherein the at least one first process parameter influences the bending behaviour of the recording stack during the irradiating step.

A vehicle display device includes a reflection-type hologram disposed inside a windshield of a vehicle, and a projection device including an image display device outputting a display light and a regulating unit configured to regulate a diffusion angle of the display light, and to project the display light having passed through the regulating unit onto the hologram. The hologram outputs the display light projected from the projection device as diffracted light directed to an eye range of the vehicle, and the regulating unit is configured to regulate the diffusion angle of the display light to an upper limit angle or less such that the display light reflected from the windshield is directed in a direction different from the eye range.