A two-dimensional holographic image projection display method. The method includes illuminating a first modulating part of a spatial light modulator with a first incident light beam at a first incident angle with respect to a direction normal to a main surface of the spatial light modulator to form a first projection region on an imaging plane; and illuminating a second modulating part of the spatial light modulator with a second incident light beam at a second incident angle with respect to the direction normal to the main surface of the spatial light modulator to form a second projection region on the imaging plane. The first projection region abuts or partially overlaps with the second projection region at an interface substantially parallel to a lateral direction of the spatial light modulator.

A holographic projector comprises an image processing engine arranged to, a hologram engine and a display engine. The image processing engine is arranged to receive a source image for projection. The source image comprises a first colour component and a second colour component. The image processing engine is further arranged to form a first colour secondary image from the first colour component by nulling alternate pixel values of the first colour component in accordance with a first checkerboard pattern. The image processing engine is further arranged to form a second colour secondary image from the second colour component by nulling alternate pixel values of the second colour component in accordance with a second checkerboard pattern. The first checkerboard pattern is opposite to the second checkerboard pattern. The hologram engine is arranged to determine a first colour hologram corresponding to the first colour secondary image and a second colour hologram corresponding to the second colour secondary image. The display engine is arranged to form a first colour holographic reconstruction from the first colour hologram and a second colour holographic reconstruction from the second colour hologram.

A display system (300) comprising an optical system and a processing system. The optical system comprising a spatial light modulator (380), a light source, a Fourier transform lens, a viewing system (320, 330) 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 (310) corresponding to the holographic data. The viewing system is arranged to produce a virtual image (350) 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.

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).

An image projector arranged to project an image onto a display plane. The image projector comprises a processing engine, a display device, an optical element and a light source. The processing engine outputs a computer-generated diffractive pattern comprising a hologram of an image for projection and a lens function corresponding to a lens having a first optical power. The display device is arranged to display the computer-generated diffractive pattern. The optical element is disposed between the display device to the display plane. The optical element has second optical power. The light source is arranged to provide off-axis illumination of the display device in order to spatially-modulated light in accordance with the hologram and lens function. The lens function of the computer-generated diffractive pattern and the optical element collectively perform a hologram transform of the hologram such that a reconstruction of the image is formed on the display plane.

An illumination device has a coherent light source that emits coherent light beam, and an optical device that diffuses the coherent light beam, wherein the optical device comprises a first diffusion region that diffuses the coherent light beam to illuminate a first area, and a second diffusion region that diffuses the coherent light beam to display predetermined information in a second area.

Optical device, and preferably a security device for a security document, and methods for the production thereof, the device including a diffractive optical element (DOE) including a plurality of subregions, wherein each subregion is configured to produce a projected image corresponding to a frame of an animation, wherein the animation includes both a static component and a variable component, and wherein the sub-regions are arranged such that when the DOE is illuminated by a point light source and moved in at least one direction, the animation is viewable as a projected image.

A method forms an image with a reconfigurable array of mirrors. The method includes configuring the array by translating some of the mirrors such that distances of the mirrors of the array from a reference plane have a non-uniform spatial distribution. The method includes illuminating the configured array with a coherent light beam such that part of the light beam is reflected off the array and is projected on a planar viewing screen.

A phase distribution is calculated such that modulated light has a predetermined intensity distribution on a target plane and displayed on a phase modulation plane, readout light enters the phase modulation plane so as to generate the modulated light. When calculating the phase distribution, a region on the phase modulation plane is divided into N regions A.sub.1 . . . A.sub.N, with sizes set such that integration values of an intensity distribution in the regions are equal to each other. Further, a region on the target plane is divided into N regions B.sub.1 . . . B.sub.N, with sizes set such that integration values of an intensity distribution in the regions are equal to each other. The phase distribution is calculated by obtaining an optical path length from the region A.sub.n to the region B.sub.n, and determining the phase of the region A.sub.n based on the optical path length.

There is provided a holographic projector comprising a hologram engine and a controller. The hologram engine is arranged to provide a hologram comprising a plurality of hologram pixels. Each hologram pixel has a respective hologram pixel value. The controller is arranged to selectively-drive a plurality of light-modulating pixels so as to display the hologram. Displaying the hologram comprises displaying each hologram pixel value on a contiguous group of light-modulating pixels of the plurality of light-modulating pixels such that there is a one-to-many pixel correlation between the hologram and the plurality of light-modulating pixels.