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.

A device for data projection, comprising a holographic element to be arranged by a windshield. An imaging device comprising a first imaging system is arranged at a first angle with respect to the holographic element and configured to illuminate the holographic element at a first illumination angle with first illumination light modulated with first image data. A second imaging system is arranged at a second angle with respect to the holographic element and configured to illuminate the holographic element at a second illumination angle different from the first illumination angle with second illumination light modulated with second image data such that on the holographic element the first illumination light overlaps with the second illumination light. The holographic element comprises a first volume hologram structured to be angle-selective for light under the first illumination angle and to generate a first two-dimensional virtual image at a first fixed distance from the holographic element corresponding to the first image data, and a second volume hologram structured to be angle-selective for light under the second illumination angle and to generate a second two-dimensional virtual image at a second fixed distance from the holographic element different from the first distance corresponding to the second image data, such that the first and second images are viewable separately and simultaneously by a person.

Several unique configurations for interferometric recording of volumetric phase diffractive elements with relatively high angle diffraction for use in waveguides are disclosed. Separate layer EPE and OPE structures produced by various methods may be integrated in side-by-side or overlaid constructs, and multiple such EPE and OPE structures may be combined or multiplexed to exhibit EPE/OPE functionality in a single, spatially-coincident layer. Multiplexed structures reduce the total number of layers of materials within a stack of eyepiece optics, each of which may be responsible for displaying a given focal depth range of a volumetric image. Volumetric phase type diffractive elements are used to offer properties including spectral bandwidth selectivity that may enable registered multi-color diffracted fields, angular multiplexing capability to facilitate tiling and field-of-view expansion without crosstalk, and all-optical, relatively simple prototyping compared to other diffractive element forms, enabling rapid design iteration.

A method for customizing a head mounted device adapted to generate a virtual image for a wearer, the method comprises: obtaining a 3D eye pupil position of the wearer in a reference frame and corresponding to a predetermined gaze direction, and customizing the head-mounted device based on the 3D eye pupil position so that the position of a focus area (EMB) at least partly coincides with the position of the eye pupil in the predetermined gaze direction, wherein customizing the head-mounted device comprises controlling a recording of a holographic mirror based on the 3D eye pupil position in the reference frame.

An optical system comprises an optically transmissive substrate comprising a metasurface which comprises a grating comprising a plurality of unit cells. Each unit cell comprises a laterally-elongated first nanobeam having a first width; and a laterally-elongated second nanobeam spaced apart from the first nanobeam by a gap, the second nanobeam having a second width larger than the first width. A pitch of the unit cells is 10 nm to 1 μm. The heights of the first and the second nanobeams are: 10 nm to 450 nm where a refractive index of the substrate is more than 3.3; and 10 nm to 1 μm where the refractive index is 3.3 or less.

A diffractive optical element according to the invention includes a holographic element configured to deflect incident light, a first substrate provided on one surface side of the holographic element, a first dielectric film provided between the first substrate and the holographic element, a second dielectric film provided on another surface side of the holographic element, and a third dielectric film provided on a side surface side of the holographic element.

There is provided a method of projection using an optical element (502,602) having spatially variant optical power. The method comprises combining Fourier domain data representative of a 2D image with Fourier domain data having a first lensing effect (604a) to produce first holographic data. Light is spatially modulated (504,603a) with the first holographic data to form a first spatially modulated light beam. The first spatially modulated light beam is redirected using the optical element (502,602) by illuminating a first region (607) of the optical element (602) with the first spatially modulated beam. The first lensing effect (604a) compensates for the optical power of the optical element in the first region (607). Advantageous embodiments relate to a head-up display for a vehicle using the vehicle windscreen (502,602) as an optical element to redirect light to the viewer (505,609).

A manufacturing system for fabricating self-aligned grating elements with a variable refractive index includes a patterning system, a deposition system, and an etching system. The manufacturing system performs a lithographic patterning of one or more photoresists to create a stack over a substrate. The manufacturing system performs a conformal deposition of a protective coating on the stack. The manufacturing system performs a deposition of a first photoresist of a first refractive index on the protective coating. The manufacturing system performs a removal of the first photoresist to achieve a threshold value of first thickness. The manufacturing system performs a deposition of a second photoresist of a second refractive index on the first photoresist. The second refractive index is greater than the first refractive index. The manufacturing system performs a removal of the second photoresist to achieve a threshold value of second thickness to form a portion of an optical grating.

Embodiments described herein relate to methods of forming gratings with different slant angles on a substrate and forming gratings with different slant angles on successive substrates using angled etch systems. The methods include positioning portions of substrates retained on a platen in a path of an ion beam. The substrates have a grating material disposed thereon. The ion beam is configured to contact the grating material at an ion beam angle θ relative to a surface normal of the substrates and form gratings in the grating material. The substrates are rotated about an axis of the platen resulting in rotation angles ϕ between the ion beam and a surface normal of the gratings. The gratings have slant angles θ′ relative to the surface normal of the substrates. The rotation angles ϕ selected by an equation ϕ=cos.sup.−1(tan(θ′)/tan(θ)).

Provided is a multi-image display apparatus including an image forming device configured to form a first image, a first polarization plate configured to transmit a first polarization component of the first image provided from the image forming device, a second polarization plate configured to transmit a second polarization component of a second image that is provided from a path different from the first image, the second polarization component being different from the first polarization component, a screen configured to reflect and diffuse the first image, and transmit the second image, and a polarization selective lens configured to focus the first image having the first polarization component, and transmit the second image having the second polarization component without refraction.