G03H1/0248

Beam divergence and various collimators for holographic or stereoscopic displays
11385594 · 2022-07-12 · ·

A holographic display with an illumination device, an enlarging unit and a light modulator. The illumination device includes at least one light source and a light collimation unit, the light collimation unit collimates the light of the at least one light source and generates a light wave field of the light that is emitted by the light source with a specifiable angular spectrum of plane waves, the enlarging unit is disposed downstream of the light collimation unit, seen in the direction of light propagation, where the enlarging unit includes a transmissive volume hologram realising an anamorphic broadening of the light wave field due to a transmissive interaction of the light wave field with the volume hologram, and the light modulator is disposed upstream or downstream of the anamorphic enlarging unit, seen in the direction of light propagation.

DETECTION DEVICE HAVING AN IMAGE CAPTURING DEVICE AND A CARRIER MEDIUM, AND DETECTION SYSTEM INCLUDING SUCH A DETECTION DEVICE AND A DEVICE WITH A SCREEN
20220221772 · 2022-07-14 · ·

A carrier medium embodied as a light guide has an input coupling region and an output coupling region, each of which are embodied as a holographic element. The carrier medium forms a cover plate for an image display region of a screen and the input coupling region is at least one partial region of the cover plate surface. Light incident on the input coupling region from the surroundings is coupled into the carrier medium, transmitted to the output coupling region by internal reflection and is in turn coupled out from the output coupling region. The coupled-out light is captured by an image capturing device and used to generate image data correlated with the captured light.

Illumination device for vehicles

Light-emitting devices for motor vehicles are provided, which comprise a reflection hologram. A light-guiding body is provided to direct light from a light source arrangement onto the hologram.

REFRACTIVE INDEX MODULATION MODIFICATION IN A HOLOGRAPHIC GRATING

Techniques disclosed herein relate to modifying refractive index modulation in a holographic optical element, such as a holographic grating. According to certain embodiments, a holographic optical element or apodized grating includes a polymer layer comprising a first region characterized by a first refractive index and a second region characterized by a second refractive index. The holographic optical element or apodized grating includes a plurality of nanoparticles dispersed in the polymer layer. The nanoparticles have a higher concentration in either the first region or the second region. In some embodiments, the nanoparticles may be configured to increase the refractive index modulation. In some embodiments, the nanoparticles may be configured to apodize the grating by decreasing the refractive index modulation proximate to sides of the grating. The refractive index may be modulated by applying a monomer reservoir buffer layer to the polymer layer, either before or after hologram fabrication.

Systems, devices, and methods for aperture-free hologram recording
11409238 · 2022-08-09 · ·

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.

Three-dimensional displays using electromagnetic field computations

Methods, apparatus, devices, and systems for three-dimensional (3D) displaying objects are provided. In one aspect, a method includes obtaining data including respective primitive data for primitives corresponding to an object, determining an electromagnetic (EM) field contribution to each element of a display for each of the primitives by calculating an EM field propagation from the primitive to the element, generating a sum of the EM field contributions from the primitives for each of the elements, transmitting to each of the elements a respective control signal for modulating at least one property of the element based on the sum of the EM field contributions, and transmitting a timing control signal to an illuminator to activate the illuminator to illuminate light on the display, such that the light is caused by the modulated elements of the display to form a volumetric light field corresponding to the object.

NB controller and form factors
11402800 · 2022-08-02 ·

A system includes a plurality of optical identifiers and a reader for the optical identifiers. Each optical identifier has an optical substrate and a volume hologram (e.g., with unique data, such as a code page) in the optical substrate. The reader for the optical identifiers includes a laser, and a camera. The laser is configured to direct laser light into a selected one of the optical identifiers that has been placed into the reader to produce an image of the associated volume holograms at the camera. The camera is configured to capture the image. The captured image may be stored in a digital format by the system.

Holographic pattern generation for head-mounted display (HMD) eye tracking using a diffractive optical element

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.

Systems and methods for fabricating a multilayer optical structure

Systems and methods for fabricating optical elements in accordance with various embodiments of the invention are illustrated. One embodiment includes a method for fabricating an optical element, the method including providing a first optical substrate, depositing a first layer of a first optical recording material onto the first optical substrate, applying an optical exposure process to the first layer to form a first optical structure, temporarily erasing the first optical structure, depositing a second layer of a second optical recording material, and applying an optical exposure process to the second layer to form a second optical structure, wherein the optical exposure process includes using at least one light beam traversing the first layer.

Sensing and feedback for the formation of complex three-dimensional acoustic fields

An apparatus includes a precursor dispenser for dispensing a precursor material into a workspace, one or more acoustic sources configured to direct acoustic waves towards the workspace to provide acoustic fields that arrange the precursor material in a three-dimensional shape in the workspace, one or more sensors configured to detect a distribution of the precursor material in the workspace, and an electronic controller in communication with the precursor dispenser, the one or more acoustic sources, and the one or more sensors, the electronic controller being programmed to cause the one or more acoustic sources to adjust the acoustic fields to reduce deviations in the distribution of the precursor material from the three-dimensional shape in the workspace.