A device for manufacturing a replica hologram, comprising a holder for a light-sensitive recording material, into which the replica hologram is to be imprinted, a holder for a master hologram, as well as a lighting device for generating light for exposing the master hologram, the color of the light generated by the lighting device being variable, and the lighting device comprising optics for exposing the master hologram with the aid of the light generated by the lighting device, the device being designed in such a way that the light emanating from the master hologram impinges on the recording material to manufacture the replica hologram.

A design screen and at least one detection device with an image capturing device and a carrier medium are provided in an external lighting device for a motor vehicle. The carrier medium is a flat waveguide on which a coupling region and a decoupling region are provided. The carrier medium is adapted to the surface shape of the design screen. The coupling region and the decoupling region are each a holographic element. Light incident on the external lighting device from the surroundings is coupled into the carrier medium via the coupling region, is transported to the decoupling region by internal reflection in the waveguide, and is decoupled at the decoupling region. The image capturing device detects the decoupled light and provides image data which correlates to the detected light.

An optical element is configured to be worn in front of an eye of a wearer. The optical element has two main surfaces and includes at least one holographic diffusive element having diffusive properties resulting from spatial variations of refractive index of said holographic diffusive element. The spatial variation of refractive index is greater than 0.001 at at least one given wavelength, on a distance less than 30 μm. An optical equipment includes the optical element and methods for recording a holographic medium onto an optical lens.

A display device for representing two-dimensional and/or three-dimensional objects or scenes, having at least one spatial light modulation device having pixels for modulating light, at least one optical system, and at least one light guiding device. Light beams originating from the individual pixels of the spatial light modulation device are incident on the at least one light guiding device at different angles on average in relation to the surface of the at least one light guiding device and can be coupled therein, whereby a coupling angular spectrum is definable. The light beams propagating in the at least one light guiding device can be coupled out of the at least one light guiding device at different angles on average in relation to an observer region, whereby a decoupling angular spectrum is definable. The decoupling angular spectrum is enlarged in comparison to the coupling angular spectrum.

A replication tool for use in preparing a holographic film by replication, comprising a base structure having a structure body and a channel configured to receive at least one of a laminated glazing and a master holographic film assembly.

A method for producing a computer-generated hologram including producing a reference beam, producing an object beam, applying computer-generated information regarding the hologram to the object beam, overlapping the object beam and the reference beam on or in a light-sensitive recording medium in order to apply the hologram by exposure, wherein several portions of the light-sensitive recording medium are exposed, one after the other, to the object beam and the reference beam simultaneously in order to produce a plurality of sub-holograms, wherein the angle of incidence at which the reference beam hits the surface of a first portion of the recording medium is different from the angle of incidence at which the reference beam hits the surface of a second portion of the recording medium. A change in the angle of incidence of the reference beam is achieved by changing the point of incidence of the reference beam on a lens.

A display device according to an embodiment of the present disclosure includes: a transparent screen; one or more imaging units; and a video projection unit that acquires positional information regarding a predetermined subject included in each of captured images obtained by the one or more imaging units and then irradiates the transparent screen with video light on the basis of the positional information to cause predetermined video to appear on the transparent screen for the subject.

A laminated pane includes first and second panes, a layer stack arranged therebetween including a first thermoplastic intermediate layer, a separating layer, a photopolymer layer with at least one holographic element, a carrier layer, and a second thermoplastic intermediate layer, wherein the photopolymer layer has a thickness of 5 μm to 50 μm, the carrier layer contains polyethylene terephthalate (PET), polyethylene (PE), polymethyl methacrylate (PMMA), polycarbonate (PC), polyamide (PA), polyvinyl chloride (PVC), and/or cellulose triacetate (TAC) and has a thickness of 20 μm to 100 μm, wherein the carrier layer is arranged directly adjacent the photopolymer layer, and the separating layer contains polyethylene (PE), polyvinyl chloride (PVC), and/or polymethyl methacrylate (PMMA) and has a thickness of 10 μm to 300 μm.

Typical waveguides rely on total internal reflection between the outer surfaces of substrates, which can make them highly susceptible to beam misalignment caused by nonplanarity of the substrates. In the manufacturing of the glass sheets commonly used for substrates, ripples can occur during the stretching and drawing of glass as it emerges from a furnace. Although glass manufacturers try to minimize ripples using predictions from mathematical models, it is difficult to totally eradicate the problem from the glass manufacturing process. Typically, these beam misalignments manifest themselves as image distortions and non-uniformities in the output illumination from the waveguide. Many embodiments of the invention are directed toward optically efficient, low cost solutions to the problem of controlling output image quality in waveguides manufactured using commercially available substrate glass and to the problem of compensating the image distortions and non-uniformity of curved waveguides.

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.