Systems, devices, and methods for aperture-free hologram recording are described. The apertures typically used for hologram recording create unwanted secondary holograms by diffracting light. Aperture-free hologram recording eliminates these unwanted secondary holograms. Aperture-free hologram recording includes applying a mask to the holographic recording medium. The mask controls the size of the recorded hologram like an aperture but does not create unwanted secondary holograms. Hologram fringes are only present in the desired recording area and a thin boundary region. The mask may be present during recording, or the mask may be used to pre-bleach the holographic recording medium. Pre-bleaching the holographic recording medium renders a portion of the holographic recording medium insensitive to light, the hologram is recorded in the light-sensitive portions of the holographic recording medium.

A method of manufacturing a holographic optical element, including: irradiating a first surface of a photosensitive substrate with a first layer, and irradiating a second surface of the photosensitive substrate with a second laser. The light emitted by the first laser is spread in an irradiation direction and the light emitted by the second laser is collected in the irradiation direction to form a plurality of groups and a plurality of overlapping angles formed by a progress direction of the light emitted by the first laser and the progress direction of the light emitted by the second laser at a predetermined location of a photosensitive area, and each of the plurality of the overlapping angles are different from each other. A display device including the holographic optical element measured using this method.

The invention relates to an apparatus (200, 300, 400, 600) for producing volume reflection holograms with substrate-guided reconstruction beams, comprising: at least one transparent, planar carrier element (210, 310, 410, 610) comprising a first flat side (210.1) and a further flat side (210.2), at least one master element (206, 306, 406, 606) arrangeable at the first flat side (210.1) of the carrier element (210, 310, 410, 610) and at least one optical input coupling element (102, 202, 302, 402, 602) configured to optically couple a light beam (214, 216), wherein provision is made of at least one coupling portion (104, 204, 304, 404, 604) configured to mechanically establish an optical contact between the input coupling element (102, 202, 302, 402) and at least one holographic recording medium (208, 308, 408) providable on the further flat side (210.2) of the carrier element (210, 310, 410) or configured to mechanically establish an optical contact between the further flat side of the carrier element (610) and at least one holographic recording medium (608) providable on a flat side (605) of the optical input coupling element (602), wherein at least the coupling portion (104, 204, 304, 404, 604) is formed from a material with a shear modulus of between 1000 Pa and 50 MPa, preferably of between 30,000 Pa and 30 MPa.

Provided are 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, a second transparent member, and an emission section. The first transparent member includes a diffusion surface for diffusing light incident on respective points. The second transparent includes a control surface and is integrated with the first transparent member, 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 emits image light to the diffusion surface.

A system for making a holographic medium 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, a second set of optical elements configured to transmit the second portion of the light through for providing a second wide-field beam, and a plurality of lenses optically coupled with the second set of optical elements configured to receive the second wide-field beam and project a plurality of separate light patterns onto the optically recordable medium for forming the holographic medium.

A first layer of anisotropic material extends along a first plane and includes anisotropic components being parallel to a second plane non-parallel and non-perpendicular to the first plane. The anisotropic components are arranged in cycloidal or helical patterns. The cycloidal or helical patterns define one or more Bragg planes that are non-parallel and non-perpendicular to the first plane and either substantially parallel or substantially perpendicular to the second plane.

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 one or more diffractive optical elements 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.

Transmission and reflection mode VHOEs are designed and fabricated for use in imaging and other applications. These VHOE provide high diffraction efficiency with minimal chromatic aberrations and astigmatism across the bandwidth. The lens provides optical power within the bandwidth centered relative to several wavelengths to magnify (focus or collimate) input light and is transparent for the rest of the image spectrum. In transmission mode, two VHOE are fabricated in such a way as to introduce compensating adjustments that minimize the astigmatism and chromatic aberrations introduced by the bandwidth of the input light. Two VHOEs are required to provide an on-axis imaging system to magnify light to form an image and reduce the chromatic aberrations across the bandwidth and reduce the astigmatism while maintaining high diffraction efficiency (DE). In reflection mode, a single VHOE is configured to act as a mirror at the specified wavelength and bandwidth and to magnify light to form an image and, consequently, has minimal level of astigmatism and chromatic aberration.

A system for making a holographic medium 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, a second set of optical elements configured to transmit the second portion of the light for providing a second wide-field beam, and a plurality of prisms optically coupled with the second set of optical elements and configured to receive the second wide-field beam and project a plurality of separate light patterns onto the optically recordable medium for forming the holographic medium.

An eye-tracking system includes a holographic illuminator and a detector. The holographic illuminator includes a light source configured to provide light and a holographic medium optically coupled with the light source. The holographic medium is configured to receive the light provided from the light source and concurrently project a plurality of separate light patterns toward an eye. The detector is configured to detect a reflection of at least a subset of the plurality of separate light patterns, reflected off the eye, for determining a location of a pupil of the eye. Also disclosed is a method for determining a location of a pupil of an eye with the eye-tracking system that includes the holographic illuminator.