A method and system for reducing the effects of glare in a system comprising a picture generating unit, such as a holographic projector. The system may be a head-up display (HUD), which is configured to display a picture to a viewer, without requiring the user to look away from their usual viewpoint. The HUD system may be comprised within a vehicle. The glare in the system may be caused by light being incident on a surface comprising a screen or a window, through which the user looks at their usual viewpoint. The surface may comprise a windshield in a vehicle. The light that causes the glare may be ambient light. The method and system are provided for reducing the effects of glare in a system that comprises a waveguide in conjunction with the picture generating unit. The waveguide may be operable to act as an exit pupil expander.

An optical component comprises a metasurface comprising nanoscale elements. The metasurface is configured to receive incident light and to generate optical outputs. The geometries and/or orientations of the nanoscale elements provide a first optical output upon receiving a polarized incident light with a first polarization, and provide a second optical output upon receiving a polarized incident light with a second polarization that is different from the first polarization.

Exemplary arrangements relate to methods for recording and reproducing holograms. A method of recording a hologram in a thresholded opto-magnetic medium (7) includes producing a collimated recording beam (1) with a pulsed laser. The intensity of the recording beam is selectively modulated by passage through a modulator (2). The recording beam is spatially shaped by passage through a shaping element (15). The shaped modulated recording beam is made convergent by passage through an aspheric lens (4). The convergent beam is deflected bidirectionally with a MEMS mirror (6) that is in operative connection with the modulator, such that multiple disposed locations on a surface of the medium are exposed to a constriction of the convergent shaped recording beam, causing a change in the medium in the locations. Reconstructing the hologram is carried out by illuminating the medium with a collimated laser beam and focusing with a lens, light from the illuminated medium onto a detection matrix. Additional methods of recording and reproducing holograms utilize alternative steps.

A head mounted display (HMD) system employs a holographic element in the optical path of the HMD to direct light to a user's eye. The HMD includes a micro-display, a lightguide, and a holographic element coupled to the lightguide. The holographic element is coupled to a polarization film, and together the element and film reflect and transmit light of different polarities in a specified pattern to assist the lightguide in directing light to the user's eye. For example, the hologram and polarization film can be configured to pass R-polarized light and reflect L-polarized light, thereby directing light from the waveguide along a specified path.

A device for combining light beams which interact with adjacently arranged pixels of a light modulator, having a beam splitting component, a beam combining component, and a beam superposition component. The beam splitting component is configured such that incident light beams are split into a first subbeam and a second subbeam so that the first subbeam propagates toward a first pixel of the light modulator and the second subbeam propagates toward a second pixel of the light modulator. The beam combining component is configured and arranged so that the first subbeam and the second subbeam are combined after interaction with pixels of the light modulator. The beam splitting component and the beam combining component are configured and arranged in such a way that a sum of optical path lengths of the first subbeam and the second subbeam is respectively constant for different angles of incidence.

A system includes a diffractive optical element configured to receive a first beam and a second beam interfering with one another to generate a first interference pattern. The diffractive optical element is also configured to forwardly diffract the first beam and the second beam to output a third beam and a fourth beam. The third beam and the fourth beam interfere with one another to generate a second interference pattern. The system also includes a detector configured to detect the second interference pattern.

The present invention relates to an inline scanning holography system for a phosphor and a transmitter. According to the present invention, the inline scanning holography system includes a polarization sensitive lens that receives a linearly polarized beam and generates a first spherical wave of right-handed circular polarized light having a negative focal length and a second spherical wave of left-handed circular polarized light having a positive focal length, a polarizer that passes only a beam component in a predetermined polarization direction therethrough among components of the generated first and second spherical waves, a scanning unit for scanning a phosphor by using an interference beam generated between the first and second spherical waves passing through the polarizer, and a first photodetector that detects a fluorescent beam diverged from the phosphor. According to the present invention, a high-efficiency and high-quality optical scanning holography for a phosphor or a transmitter may be implemented.

A holographic security or identification device (10) comprises an object, or a flexible substrate (12) configured to be conformable to a desired, curved shape; and a plurality of structures (14) formed on or in the object to have a desired curved configuration, or formed in or associated with the substrate and arranged to adopt a desired curved configuration when the substrate is conformed to a desired shape, wherein the plurality of structures (14) are configured to receive light (20) of a selected at least one wavelength or range of wavelengths and to produce, using the received light, a desired holographic image (22) for security or identification purposes when in the desired configuration.

A polarization volume grating (PVG) includes a bulk, birefringent medium characterized by a plurality of helical structures with helix axes and a periodicity Λ.sub.y and an anisotropic alignment material having a rotatable optical axis, disposed on a top or bottom surface of the medium. The PVG is characterized in that the optical axis of the alignment material has a continuously rotated optical axis orientation in a plane of the material surface and a periodicity Λ.sub.x, wherein the helix axes are normal to the optical axes in the alignment material surface, further wherein the birefringent medium is characterized by a plurality of controllably slanted refractive index planes having a slant angle φ=±arctan (Λ.sub.y/Λ.sub.x) and a Bragg period Λ.sub.B. Fabrication methods are disclosed.

The invention relates to a system (1) for observing objects, including: a light source (3), a holder (12) able to receive a translucent or opaque substrate, a detector (7) able to collect the backscattered light from the interaction between the light emitted by light source (3) and the objects, a polarization splitter (9), and a quarter-wave plate (10), the splitter (9) and the quarter-wave plate (10) being arranged so that the splitter (9) directs the light emitted by the light source (3) toward the solid substrate and directs the backscattered light from the interaction between the light emitted by the light source (3) and the objects toward the detector (7).