A method and a system thereof for producing a digital holographic screen based on multi-hogel printing are proposed. The system includes a light source unit including lasers, a dichroic mirror for RGB three color matching, mirrors, a beam splitter, and an optical shutter, an object beam unit including a spatial filter, a lens, and a mirror, a reference beam unit including a spatial filter, a lens, and a mirror, a diffuser fixing unit including a diffuser holder and a diffuser positioned between the object beam unit and a recording material and configured to scatter and diffuse the object beam, a photomask movement unit including a photomask holder, an XY-translation stage, and a photomask positioned between the reference beam unit and the recording medium and on which a grid-shaped on/off binary pattern is printed, and a controller configured to control the optical shutter and the XY-translation stage.

A holographic lighting apparatus includes at least two channels for the respective associated lighting functions. Each channel includes an edge-lit arrangement with an incoupling surface for coupling light from a light source into the arrangement, and an outcoupling surface; and a light source. The edge-lit arrangements of the channels are all included in a monolithic component having a common outcoupling surface, and each channel is arranged so as to be rotated about a surface normal of the outcoupling surface along an azimuthal arrangement angle. The component has at least one holographic structure for generating the lighting function of the relevant channel when said structure is illuminated by the light source of the channel. Also provided are a vehicle including a corresponding lighting apparatus, the use of the lighting apparatus as a display in a vehicle, and the lighting apparatus as an LED collimator.

There is provided a holographic optical element including: a hologram portion including a plurality of groups of unit regions, each group of unit regions of the hologram portion being configured to produce a respective holographic image under a respective light illumination having a respective predetermined wavelength; and a colour filter portion formed on the hologram portion, the colour filter portion including a plurality of groups of unit regions, each group of unit regions of the colour filter portion being arranged on a corresponding group of the plurality of groups of unit regions of the hologram portion, whereby the plurality of groups of unit regions of the colour filter portion is spatially arranged to form a predetermined colour image. There is also provided a method of forming the holographic optical element. There is further provided an article having optical security incorporated therein.

A method of computing a hologram by determining the wavefronts at the approximate observer eye position that would be generated by a real version of an object to be reconstructed. In normal computer generated holograms, one determines the wavefronts needed to reconstruct an object; this is not done directly in the present invention. Instead, one determines the wavefronts at an observer window that would be generated by a real object located at the same position of the reconstructed object. One can then back-transforms these wavefronts to the hologram to determine how the hologram needs to be encoded to generate these wavefronts. A suitably encoded hologram can then generate a reconstruction of the three-dimensional scene that can be observed by placing one's eyes at the plane of the observer window and looking through the observer window.

Disclosed herein is a holographic display which enables stereoscopic display of colors by changing a structure and mitigates a flickering effect by lowering the response speed. The holographic display may deliver an image to different positions for the left eye and right eye at the same time, thereby lowering the frequency necessary for supply of holographic image information. Thereby, the holographic display may address the issues of the afterimage effect and flickering effect in a liquid crystal panel-based spatial light modulator.

There is provided a lighting device arranged to produce a controllable light beam for illuminating a scene. The device comprises an addressable spatial light modulator arranged to provide a selectable phase delay distribution to a beam of incident light. The device further comprises Fourier optics arranged to receive phase-modulated light from the spatial light modulator and form a light distribution. The device further comprises projection optics arranged to project the light distribution to form a pattern of illumination as said controllable light beam.

A holographic display device includes a backlight unit for emitting light and a spatial light modulator. The spatial light modulator includes a plurality of pixels and a color filter layer including a plurality of color filter groups. The pixels are arranged in a zigzag form and are configured to modulate at least one of the amplitude and phase of the light. Each of the color filter groups includes a first sub-group including a plurality of first color filters, a second sub-group including a plurality of second color filters, and a third sub-group including a plurality of third color filters, and each of the pixels is aligned with one of the first color filters, the second color filters, and the third color filters of the color filter layer.

A method of generating a color image of a sample includes obtaining a plurality of low resolution holographic images of the sample using a color image sensor, the sample illuminated simultaneously by light from three or more distinct colors, wherein the illuminated sample casts sample holograms on the image sensor and wherein the plurality of low resolution holographic images are obtained by relative x, y, and z directional shifts between sample holograms and the image sensor. Pixel super-resolved holograms of the sample are generated at each of the three or more distinct colors. De-multiplexed holograms are generated from the pixel super-resolved holograms. Phase information is retrieved from the de-multiplexed holograms using a phase retrieval algorithm to obtain complex holograms. The complex hologram for the three or more distinct colors is digitally combined and back-propagated to a sample plane to generate the color image.

A method of computing a hologram by determining the wavefronts at the approximate observer eye position that would be generated by a real version of an object to be reconstructed. In normal computer generated holograms, one determines the wavefronts needed to reconstruct an object; this is not done directly in the present invention. Instead, one determines the wavefronts at an observer window that would be generated by a real object located at the same position of the reconstructed object. One can then back-transforms these wavefronts to the hologram to determine how the hologram needs to be encoded to generate these wavefronts. A suitably encoded hologram can then generate a reconstruction of the three-dimensional scene that can be observed by placing one's eyes at the plane of the observer window and looking through the observer window.

A holographic display apparatus for providing an expanded viewing window includes a spatial filter configured to separate a plurality of holographic images generated by the hologram pattern displayed on the spatial light modulator from a plurality of lattice spots generated by a physical structure of the spatial light modulator. The spatial filter includes a plurality of color filters or a plurality of dichroic mirrors separating a first color image, a second color image, and a third color image from a first color lattice spot, a second color lattice spot, and a third color lattice spot.