A wearable heads-up display includes a support structure that in use is worn on a head of a user, a scanning laser projector carried by the support structure, and a holographic optical element carried by the support structure. The holographic optical element includes a set of holograms formed in one or more layers of holographic material. The set of holograms includes a red hologram that is exclusively responsive to red laser light incident thereon over a first range of angles of incidence, a green hologram that is exclusively responsive to blue laser light incident thereon over the first range of angles of incidence, and a blue hologram that is exclusively responsive to green laser light incident thereon over the first range of angles of incidence.

The present disclosure relates to a holographic reproducing apparatus comprising: a light source configured to supply a reproducing light beam to be incident to a photorefractive crystal, wherein the photorefractive crystal has holographic images recorded therein in a plurality of different angles respectively; a reflective mirror configured to reflect the reproducing light beam emitted from the light source to the photorefractive crystal; and a driving mechanism connected to the reflective mirror and configured to drive the reflective mirror to move on a plane elliptical arc, the plane elliptical arc is defined by using the light source and the photorefractive crystal as two mathematical focuses and using a predetermined constant, so that an incident angle of the reproducing light beam to be incident to the photorefractive crystal varies to form a plurality of reproducing light beams in different angles to be incident to the photorefractive crystal in sequence.

Systems, devices, and methods for engineering the eyebox of a display using multiple heterogeneous exit pupils are described. The eyebox of a display includes at least two heterogeneous exit pupils that are different from one another in terms of size and/or shape. Heterogeneous exit pupils may overlap, one may encompass another, or they may be completely spatially-separated from one another. Such configurations enable specific eyebox and/or visual display configurations that can be advantageous in certain applications. An example in which a scanning laser-based wearable heads-up virtual retina display implements a holographic combiner that is engineered to provide multiple heterogeneous exit pupils is described.

An optical data-recording system comprises a laser, a dynamic digital hologram, an electronic controller, and a scanning mechanism. The dynamic digital hologram includes a plurality of holographic zones, and is configured to direct the irradiance received thereon to an optical recording medium. The electronic controller is operatively coupled to the dynamic digital hologram and configured to control the irradiance directed from each of the holographic zones. The scanning mechanism is configured to change a relative positioning of the laser versus the dynamic digital hologram so that each of the holographic zones is irradiated in sequence by the laser.

Systems, devices, and methods for spatial multiplexing in holographic optical elements (HOEs) are described. A spatially-multiplexed HOE includes multiple spatially-separated holographic regions and each spatially-separated region applies a respective optical function to light that is incident thereon. An exemplary application as a spatially-multiplexed holographic combiner (SMHC) in a scanning laser-based wearable heads-up display (WHUD) is described. In this exemplary application, a scanning laser projector directs multiple light signals over the area of the SMHC and the SMHC converges the light signals towards multiple spatially-separated exit pupils at or proximate the eye of the user. The particular exit pupil at the eye of the user towards which any particular light signal is converged by the SMHC depends on the particular region of the SMHC upon which the light signal is incident. Such may be useful in engineering particular eyebox and/or user interface display configurations in the operation of the WHUD.

For comfortable viewing of a 3-D scene at various viewing angles, a display having a large tracking range for a variable viewer distance is required. A controllable light-influencing element deflects light in coarse steps in a viewer range. Within said steps, the light is deflected by a further controllable light-influencing element continuously or with fine gradation. The light modulation device is suitable in holographic or autostereoscopic displays for guiding the visibility ranges of the image information to be displayed so as to follow the eyes of the viewers.

The invention relates to a display device, in particular a head-mounted display or hocular, having a spatial light modulator and a controllable light-deflecting device for generating a multiple image of the spatial light modulator, which consists of segments, the multiple image being produced at least with a predefinable number of segments which determines the size of a visible area within which a 3D-scene holographically encoded in the spatial light modulator can be reconstructed for observation by an eye of an observer.

An optical device including a hologram recording medium that can reproduce an image of a reference member and an irradiation unit that emits a coherent light beam to the optical device. The irradiation unit includes a light source for emitting a coherent light beam and a scanning device capable of adjusting a reflection angle of the coherent light beam emitted from the light source and that makes a reflected coherent light beam scan the hologram recording medium. The light source has light sources for emitting coherent light beams having different wavelength ranges. The hologram recording medium has a plurality of recording areas to be scanned with a plurality of coherent light beams reflected by the scanning device, respectively. Each of the plurality of recording areas has an interference fringe that diffracts a coherent light beam of the corresponding wavelength range.

A holographic image display device includes a backlight for emitting light. An optical path adjuster includes a plurality of electrowetting prisms. Each of the plurality of electrowetting prisms is configured to adjust an optical path of the light. A spatial light modulator includes a plurality of pixels. Each of the plurality of pixels is configured to modulate an amplitude or a phase of the light.

The present invention generally extends to methods, systems, and devices that advantageously employ holograms to store and retrieve information about objects, and to compare objects. Methods include generating first and second holograms of image spectral cross sections comparing the holograms and using a photometer to analyze the comparison result. Computer program products are described for use in differentiating spectral components of spatial cross sections of image pixels.