An interference structure having a nanovoided hologram material is described. The nanovoided hologram material may have an index of refraction difference of approximately 0.4. The interference structure may include about 10% to 90% nanovoids by volume. The interference structure may be formed using a mixture of a monomer, an initiator, and solvent. The mixture may be disposed on a substrate and irradiated with two sources of light spaced apart from each other and shining on the same region of the mixture to generate an interference pattern in the mixture, leading to the selective polymerization of regions of the mixture where there is constructive interference of light. Various other devices, methods, and systems are also disclosed.

A grating coupler may be fabricated by exposing a photopolymer layer to grating forming light for forming periodic refractive index variations in the photopolymer layer. The photopolymer layer may be exposed to apodization light for reducing an amplitude of the periodic refractive index variations in a spatially-selective manner. The apodization may also be achieved or facilitated by subjecting outer surface(s) of the photopolymer layer to a chemically reactive agent that causes the refractive index contrast to be reduced near the surface(s) of application. The apodized refractive index profile of the gratings facilitates the reduction of optical crosstalk between different gratings of the grating coupler.

A holographic projector comprises an image processing engine arranged to, a hologram engine and a display engine. The image processing engine is arranged to receive a source image for projection. The source image comprises a first colour component and a second colour component. The image processing engine is further arranged to form a first colour secondary image from the first colour component by nulling alternate pixel values of the first colour component in accordance with a first checkerboard pattern. The image processing engine is further arranged to form a second colour secondary image from the second colour component by nulling alternate pixel values of the second colour component in accordance with a second checkerboard pattern. The first checkerboard pattern is opposite to the second checkerboard pattern. The hologram engine is arranged to determine a first colour hologram corresponding to the first colour secondary image and a second colour hologram corresponding to the second colour secondary image. The display engine is arranged to form a first colour holographic reconstruction from the first colour hologram and a second colour holographic reconstruction from the second colour hologram.

An imaging flow cytometer device includes a housing holding a multi-color illumination source configured for pulsed or continuous wave operation. A microfluidic channel is disposed in the housing and is fluidically coupled to a source of fluid containing objects that flow through the microfluidic channel. A color image sensor is disposed adjacent to the microfluidic channel and receives light from the illumination source that passes through the microfluidic channel. The image sensor captures image frames containing raw hologram images of the moving objects passing through the microfluidic channel. The image frames are subject to image processing to reconstruct phase and/or intensity images of the moving objects for each color. The reconstructed phase and/or intensity images are then input to a trained deep neural network that outputs a phase recovered image of the moving objects. The trained deep neural network may also be trained to classify object types.

Embodiments of the present disclosure include apparatuses and method for a stacked light emitting diode (LED) hologram display. A stacked LED hologram display can include a first array of LEDs that are configured to emit red light received by a meta-optics panel configured to display a first portion of a holographic image, a second array of LEDs that are configured to emit green light received by a meta-optics panel configured to display a second portion of a holographic image, and a third array of LEDs that are configured to emit blue light received by a meta-optics panel configured to display a third portion of a holographic image. The stacked LED hologram display can include a number of actuators configured to adjust a position of a first array of LEDs in first direction and a second direction, adjust a position of a second array of LEDs in the first direction and the second direction, and adjust a position of a third array of LEDs in the first direction and the second direction.

A holographic imaging device is disclosed. In one aspect, the holographic imaging device comprises an imaging unit comprising at least two light sources, wherein the imaging unit is configured to illuminate an object by emitting at least two light beams with the at least two light sources. A first and second light beams have different wave-vectors and wavelengths. The holographic imaging device further comprises a processing unit configured to obtain at least two holograms of the object by controlling the imaging unit to sequentially illuminate the object with respectively the first light beam and the second light beam, construct at least two 2D image slices based on the at least two holograms, wherein each 2D image slice is constructed at a determined depth within the object volume, and generate a three-dimensional image of the object based on a combination of the 2D image slices.

A backlight device includes: a light source to emit coherent light; an optical path difference generator on the light source, the optical path difference generator including an incident surface and a plurality of light emitting surfaces, the light emitting surfaces being parallel to the incident surface and having different separation distances from the incident surface; a light condenser on the optical path difference generator; a diffuser on the light condenser; and a collimator on the diffuser.

A display panel (1) comprising a body of optical material, the body having at least one optical image recorded therein in an encoded manner, wherein the image is selectively reconstructable and viewable (5, 6, 7) by illuminating the panel (1) using at least one light source (3a, 3b, 3c) under selected illumination conditions, wherein the image is reconstructable and viewable (5, 6, 7) such that at least one first optical property or parameter of the reconstructed image (e.g. its geometry, position in space, colour, its dynamic appearance) is selectable in value from amongst variable values of the at least one first optical property or parameter, or whose value is actively modifiable over time, as a function of or in dependence on the value of at least one second optical property or parameter of the illumination conditions of the at least one light source (e.g. its/their position(s) or spacing(s) relative to the panel (1), its/their colour, brightness/optical intensity, polarisation, direction of light ray propagation, application of a scanning technique to illuminate the panel (1)) which is selectable from amongst variable values thereof or which is actively modifiable in value over time.

A holographic display system including a first spatial light modulator panel and a second spatial light modulator panel is provided. The first spatial light modulator panel is configured to receive a first light with a first color, and generate a first diffracted light with the first color. The second spatial light modulator panel is configured to receive a second light with a second color and a third light with a third color, and respectively generate a second diffracted light with the second color and a third diffracted light with the third color. The first color, the second color, and the third color are different colors, and the first diffracted light, the second diffracted light and the third diffracted light form holographic images. A method for generating holographic images is also provided.

A lighting device, in particular a rear luminaire, for a vehicle is provided. The lighting device has a hologram and a light source for illuminating the hologram. An image, more particularly a real image, is thereby generated, which can also lie outside the physical boundaries of the lighting device.