A system for making a holographic medium includes a light source configured to provide light and a beam splitter configured to separate the light into a first portion of the light and a second portion of the light that is spatially separated from the first portion of the light. The system also includes a first set of optical elements configured to transmit the first portion of the light for providing a first wide-field beam onto an optically recordable medium, a second set of optical elements configured to transmit the second portion of the light through for providing a second wide-field beam, and a plurality of lenses optically coupled with the second set of optical elements configured to receive the second wide-field beam and project a plurality of separate light patterns onto the optically recordable medium for forming the holographic medium.

A system for making a holographic medium for use in generating light patterns for eye tracking includes a light source configured to provide light and a beam splitter configured to separate the light into a first portion of the light and a second portion of the light that is spatially separated from the first portion of the light. The system also includes a first set of optical elements configured to transmit the first portion of the light for providing a first wide-field beam onto an optically recordable medium and a plurality of optical fibers configured to receive the second portion of the light and project a plurality of separate light patterns onto the optically recordable medium for forming the holographic medium.

An apparatus for manufacturing a hologram includes a holographic optical element on which a first interference pattern of a first signal beam and a first reference beam is recorded and a second interference pattern of a second signal beam modulated by a Fourier lens and a second reference beam is recorded. Also, an apparatus for reconstructing a hologram by using the holographic optical element is provided.

A main object of the present disclosure is to provide a hologram structure having excellent forgery preventability and designability. The present disclosure achieves the object by providing a hologram structure comprising: a hologram layer including a reflection type hologram forming region carrying a recorded phase type Fourier transform hologram that transforms an incident light from a point light source into a desired optical image; and a vapor deposition layer formed so as to come into contact with a concavo-convex surface of the reflection type hologram forming region of the hologram layer, and a size of the reflection type hologram forming region in plan view is in a range of 5 mm square or more and 50 mm square or less.

To provide an authentication device and method for a security medium including a reflective volume hologram having a light source disposed on the front surface side of the reflective volume hologram so that light emitted therefrom is incident on the reflective volume hologram, a first observation device disposed in a pre-designed diffraction direction of the reflective volume hologram, and a second observation device disposed in a direction other than the pre-designed diffraction direction of the reflective volume hologram. Light including a pre-designed diffraction wavelength is emitted from the light source to be incident on the reflective volume hologram, and when the light amount observed in the first observation device is larger in the diffraction wavelength than in other wavelengths, and the light amount observed in the second observation device is smaller in the diffraction wavelength than in other wavelengths, it is determined that the reflective volume hologram is genuine.

A substrate-guided holographic diffuser has a light-guide section configured to in-couple light and transmit the light within itself via total internal reflection. It can also have a brightness enhancement section that recycles non-diffracted light within the light-guide section. A hologram section that receives light from the light-guide section has a holographic structure defining acceptance conditions and is positioned relative to the internally reflected light such that the internally reflected light meets the acceptance conditions of the holographic structure. The internally reflected light is out-coupled by the holographic structure as a projected image of light scattered from a diffuser.

A method for producing a volume hologram with at least one first area in a first color and at least one second area in a second color includes, providing a volume hologram layer made of a photopolymer; arranging a master with a surface structure on the volume hologram layer; exposing the master using coherent light, wherein light which is incident on at least one first partial area of the surface of the master is diffracted or reflected in the direction of the at least one first area of the volume hologram layer and light which is incident on at least one second partial area of the surface of the master is diffracted or reflected in the direction of the at least one second area of the volume hologram, and wherein the light diffracted or reflected by the first and second partial areas differs in at least one optical property.

Provided is an image display device including a first light source configured to emit a first beam of light, a second light source configured to emit a second beam of light, a spatial light modulator configured to modulate the first beam of light and the second beam of light, a holographic optical element configured to focus, on a first focal point, the first beam of light emitted from the first light source and modulated by the spatial light modulator, and to focus, on a second focal point, the second beam of light emitted from the second light source and modulated by the spatial light modulator and a processor configured to control the first and the second light sources and the spatial light modulator.

An apparatus for manufacturing a hologram includes a holographic optical element on which a first interference pattern of a first signal beam and a first reference beam is recorded and a second interference pattern of a second signal beam modulated by a Fourier lens and a second reference beam is recorded. Also, an apparatus for reconstructing a hologram by using the holographic optical element is provided.

A purpose of the present invention is to provide an image display apparatus and an image display element that are capable of achieving excellent visual effects. The image display apparatus of the present invention includes a first transparent member (30), a second transparent member (40), and an emission section (10). The first transparent member (30) includes a diffusion surface (31) for diffusing light incident on respective points. The second transparent (40) includes a control surface (41) and is integrated with the first transparent member (30), the control surface being disposed in a manner that the control surface faces the diffusion surface, controlling propagation directions of light diffused at the respective points on the diffusion surface, and forming a virtual image of the diffusion surface. The emission section (10) emits image light to the diffusion surface (31).