A system for making a holographic medium for use in generating light patterns for eye tracking includes a light source configured to provide light and a beam splitter configured to separate the light into a first portion of the light and a second portion of the light that is spatially separated from the first portion of the light. The system also includes a first set of optical elements configured to transmit the first portion of the light for providing a first wide-field beam onto an optically recordable medium and a plurality of optical fibers configured to receive the second portion of the light and project a plurality of separate light patterns onto the optically recordable medium for forming the holographic medium.

An apparatus for manufacturing a hologram includes a holographic optical element on which a first interference pattern of a first signal beam and a first reference beam is recorded and a second interference pattern of a second signal beam modulated by a Fourier lens and a second reference beam is recorded. Also, an apparatus for reconstructing a hologram by using the holographic optical element is provided.

Provided is a digital holographic imaging apparatus, comprising: an illumination portion (10) having an illumination light emission surface (32i) for emitting coherent light of a specific wavelength as illumination light toward an object (1) side relative to the illumination light emission surface (32i), and a reference light emission surface (32r) for emitting the coherent light, as reference light, in a direction opposite to the illumination light; and an image sensor (50) located on the reference light emission surface (32r) side of the illumination portion (10) and imaging an interference pattern between object light having been modulated by the object (1) and passed through the illumination portion (10) and the reference light of the illumination light, the image sensor (50) having a pixel array (51) comprising two-dimensionally aligned pixels.

A substrate-guided holographic diffuser has a light-guide section configured to in-couple light and transmit the light within itself via total internal reflection. It can also have a brightness enhancement section that recycles non-diffracted light within the light-guide section. A hologram section that receives light from the light-guide section has a holographic structure defining acceptance conditions and is positioned relative to the internally reflected light such that the internally reflected light meets the acceptance conditions of the holographic structure. The internally reflected light is out-coupled by the holographic structure as a projected image of light scattered from a diffuser.

The present disclosure provides an in-vehicle display system and a vehicle. The in-vehicle display system includes an optical fiber holographic projection portion and a holographic image display portion. The optical fiber holographic projection portion is configured to holographically project image information of a vehicle component onto the holographic image display portion, and the holographic image display portion is configured to present an original image of the vehicle component.

An additive manufacturing device may include a material supply, a robot, and a printing head coupled to a distal end of the robot and configured to receive printing material from the material supply. The additive manufacturing device may have an IR holographic device configured to generate a targeting hologram, an IR sensor, and a controller coupled to the robot, the printing head, the IR holographic device, and the IR sensor. The controller may be configured to cause the printing head to dispense the printing material to form an object based upon the targeting hologram.

An apparatus for manufacturing a hologram includes a holographic optical element on which a first interference pattern of a first signal beam and a first reference beam is recorded and a second interference pattern of a second signal beam modulated by a Fourier lens and a second reference beam is recorded. Also, an apparatus for reconstructing a hologram by using the holographic optical element is provided.

Multiple pairs of substrate-guided wave-based holograms (SGWHs) are laminated to a common thin substrate to form a transparent substrate-guided wave-based holographic CHMSL (SGWHC) that diffracts playback LED illumination over a wide angular range. This device is made pursuant to a technique that includes the steps of recording a first set of SGWHs with one setup, that upon playback, will couple and guide the diffracted light inside the substrate, and a second set of SGWHs recorded with another setup, that will diffract and couple the guided light out.

A purpose of the present invention is to provide an image display apparatus and an image display element that are capable of achieving excellent visual effects. The image display apparatus of the present invention includes a first transparent member (30), a second transparent member (40), and an emission section (10). The first transparent member (30) includes a diffusion surface (31) for diffusing light incident on respective points. The second transparent (40) includes a control surface (41) and is integrated with the first transparent member (30), the control surface being disposed in a manner that the control surface faces the diffusion surface, controlling propagation directions of light diffused at the respective points on the diffusion surface, and forming a virtual image of the diffusion surface. The emission section (10) emits image light to the diffusion surface (31).

A substrate-guided holographic diffuser has a light-guide section configured to in-couple light and transmit the light within itself via total internal reflection. It can also have a brightness enhancement section that recycles non-diffracted light within the light-guide section. A hologram section that receives light from the light-guide section has a holographic structure defining acceptance conditions and is positioned relative to the internally reflected light such that the internally reflected light meets the acceptance conditions of the holographic structure. The internally reflected light is out-coupled by the holographic structure as a projected image of light scattered from a diffuser.