There is provided a method of projection using an optical element (502,602) having spatially variant optical power. The method comprises combining Fourier domain data representative of a 2D image with Fourier domain data having a first lensing effect (604a) to produce first holographic data. Light is spatially modulated (504,603a) with the first holographic data to form a first spatially modulated light beam. The first spatially modulated light beam is redirected using the optical element (502,602) by illuminating a first region (607) of the optical element (602) with the first spatially modulated beam. The first lensing effect (604a) compensates for the optical power of the optical element in the first region (607). Advantageous embodiments relate to a head-up display for a vehicle using the vehicle windscreen (502,602) as an optical element to redirect light to the viewer (505,609).

A phase modulation data generating unit according to the present disclosure includes: a first calculating section; and a storage section. The first calculating section calculates basic phase modulation pattern data on the basis of a partial illumination image pattern that makes it possible to generate an intended illumination image pattern having a desired luminance distribution. The basic phase modulation pattern data makes it possible for a light phase modulation device to reconstruct the partial illumination image pattern. The storage section stores the basic phase modulation pattern data calculated by the first calculating section.

An apparatus and method to produce a hologram of an object includes an electromagnetic radiation assembly configured to receive a received electromagnetic radiation, such as light, from the object. The electromagnetic radiation assembly is further configured to diffract the received electromagnetic radiation and transmit a diffracted electromagnetic radiation. An image capture assembly is configured to capture an image of the diffracted electromagnetic radiation and produce the hologram of the object from the captured image.

The present invention relates to a system and method for high quality speckle-free phase-only computer-generated holographic image projection. The present invention more particularly relates to a holographic image display system comprising a spatial light modulator to phase modulate light from at least one light source configured to illuminate said spatial light modulator and to provide a phase hologram and projection optics to project said phase modulated light to generate an image formed by said displayed hologram onto an image plane.

The disclosure provides a display system and a method for displaying a virtual image to a viewer An optical system of the disclosure includes a spatial light modulator, a light source, a Fourier transform lens, a viewing system and a processing system. The spatial light modulator is arranged to display holographic data in the Fourier domain, illuminated by the light source. The Fourier transform lens is arranged to produce a 2D holographic reconstruction in the spatial domain corresponding to the holographic data. The viewing system is arranged to produce a virtual image of the 2D holographic reconstruction. The processing system is arranged to combine the Fourier domain data representative of a 2D image with Fourier domain data representative of a phase only lens to produce first holographic data, and provide the first holographic data to the optical system to produce a virtual image.

There is provided a holographic display device, which includes a display panel including plural sub-pixels, wherein each sub-pixel includes plural subdivided pixels, and each subdivided pixel has an adjustable light transmittance; a backlight, configured to provide reference light to the display panel; a phase adjustment layer, including plural transparent phase adjustment components, wherein each phase adjustment component is configured to adjust a phase of a light ray transmitted through the phase adjustment component, and the phase adjustment components corresponding to a single sub-pixel have phase adjustment amounts different from each other; and a controller, configured to obtain a target phase of a light ray to be transmitted through each sub-pixel, and determine a target subdivided pixel, which corresponds to the target phase, in each sub-pixel, and further configured to obtain a target intensity of the light ray, and adjust a light transmittance of the target subdivided pixel.

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 display system includes a data provider, a spatial light modulator and a second cylindrical lens. The data provider is arranged to provide holographic data comprising first data corresponding to a first cylindrical lens having optical power in a first direction. The spatial light modulator is arranged to receive the holographic data, wherein the spatial light modulator is arranged to spatially-modulate received light in accordance with the holographic data. The second cylindrical lens is arranged to receive spatially-modulated light from the spatial light modulator and perform a one-dimensional Fourier transform of the received light in a second direction orthogonal to the first direction.

A method and system for forming a holographic structure in a material. The holographic structure is configured to project a selected target image in the far field under illumination of the holographic structure by a laser. The method calculates a modified design for the holographic structure that encodes a unique identifier within the holographic structure for projecting the target image. The method modifies the material by mapping features corresponding to the modified design into the material so as to form the holographic structure. A basic check of the authenticity of the material is performed by checking whether a projected replica of the target image is as expected. A more detailed check of the authenticity of the material is performed by directly inspecting the features in the holographic structure.

A phase modulation data generating unit according to the present disclosure includes: a first calculating section; and a storage section. The first calculating section calculates basic phase modulation pattern data on the basis of a partial illumination image pattern that makes it possible to generate an intended illumination image pattern having a desired luminance distribution. The basic phase modulation pattern data makes it possible for a light phase modulation device to reconstruct the partial illumination image pattern. The storage section stores the basic phase modulation pattern data calculated by the first calculating section.