The invention relates to a method for generating holograms for encoding in a spatial light modulation device for a holographic display for representing a two- and/or three-dimensional scene. The two- and/or three-dimensional scene is decomposed into object points and encoded in a hologram, which is subdivided into subholograms, in the spatial light modulation device. The object points of the scene are encoded into encoding regions on the spatial light modulation device. A size and/or shape of the encoding region is selected in relation to a size and/or shape of a subhologram, assigned to the encoding region, in such a way that crosstalk of higher diffraction orders in a virtual visibility region is reduced.

A holographic display simulation device and a holographic display simulation method are provided. A holographic display simulation device includes a processor; and a memory including one or more instructions, wherein the one or more instructions are executed by the processor, and a holographic display is simulated by using at least one of a light source part model, a spatial light modulator model, and a display optical system model that respectively model a light source part, a spatial light modulator, and a display optical system of the holographic display.

An optical security device (1) comprising a recorded or encoded representation of an optically variable image (40), the image (40) being reconstructable and viewable for security, authentication or identification purposes, the device (1) comprising: an optical structure (30) in which there is recorded or encoded a representation of the optically variable image (40) in the form of a plurality of discrete portions (e.g. 50) of the complete image (40) to be reconstructed, wherein the respective said plurality of portions (e.g. 50) of the optically variable image (40) can, when reconstructed, only be viewed in their totality by viewing the said image (40) at or over a plurality of different viewing angles or angle ranges (70) relative to the optical structure (30) and/or at or over a plurality of different angles or range of angles of illumination of the optical structure (10), and wherein the size, in at least one dimension, direction, axis or plane, of the complete image (40), when reconstructed, is greater than the corresponding size, in the same, or the respective same, dimension, direction, axis or plane, of a part of the optical structure (30) having the said plurality of portions (e.g. 50) of the image (40) collectively recorded or encoded therein.

Provided is a holographic display apparatus including: a spatial light modulator that modulates a wavefront of a reference beam to form a hologram image; an optical element arranged to change a position of a viewing window of the hologram image off-axis by a first angle; and an image processor that generates hologram data according to the position of the viewing window of the hologram image and a hologram image to be reproduced, and provides the hologram data to the spatial light modulator. The hologram image formed by the spatial light modulator is viewable from a side of the spatial light modulator.

An apparatus and method for the three-dimensional representation of scenes comprising an illumination device and a spatial light modulation device for modulating incident light. A hologram is encoded into the spatial light modulation device and the hologram is composed of individual sub-holograms, in which an object point of an object of the scene to be reconstructed by the hologram is encoded in each case. The spatial light modulation device is illuminated with substantially coherent light by the illumination device in at least one illumination section. An amplitude distribution and a phase distribution for representing the scene and amplitude values and phase values derived therefrom are determined for encoding the spatial light modulation device. The amplitude of the light incident on the spatial light modulation device in the respective illumination section is set based on at least one parameter at least determined from the amplitude values in this illumination section.

Provided is a method of generating a computer-generated hologram (CGH), the method including obtaining complex data including amplitude data of object data and phase data of the object data corresponding to a spatial light modulator (SLM) plane by propagating the object data from an image plane to the SLM plane, encoding the complex data into encoded amplitude data, and generating a CGH based on the object data including the encoded amplitude data.

A method of displaying a Computer Generated Holographic (CGH) image by a display, including setting pixel values of a Spatial Light Modulator (SLM) included in a Head Mounted Display (HMD), producing a interference based holographic image at a first location by projecting coherent light onto the SLM, and re-imaging the holographic image from the first location to form a holographic image in front of an eye of a viewer wearing the HMD. Related apparatus and methods are also described.

Provided is a method of generating a computer-generated hologram (CGH), the method including obtaining complex data including amplitude data of object data and phase data of the object data corresponding to a spatial light modulator (SLM) plane by propagating the object data from an image plane to the SLM plane, encoding the complex data into encoded amplitude data, and generating a CGH based on the object data including the encoded amplitude data.

A holographic projection operating device, holographic projection device and holographic optical module thereof are illustrated. The holographic optical module has a first and a second prism array. The first prism array has a plurality of first prisms with first faces in contact with each other to form a first optical interface. The second prism array has a plurality of second prisms with second faces in contact with each other to form a second optical interface. Light is incident on the first optical interface at a first incident angle to undergo total internal reflection and generate a first reflected ray or at a second incident angle to undergo total internal reflection and generate a second reflected ray. The first or second reflected ray enters the second prism array and hits the second optical interface at a third incident angle to undergo total internal reflection and generate a third reflected ray.

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.