G03H2225/22

Holographic Projector
20210232005 · 2021-07-29 ·

There is provided a holographic projector comprising a reflective liquid crystal display device. The reflective liquid crystal display device comprises a light-modulating layer between a first substrate and a second substrate substantially parallel to the first substrate. The light-modulating layer comprises planar-aligned nematic liquid crystals having positive dielectric anisotropy. The first substrate is substantially transparent and comprises a first alignment layer arranged to impart a first pre-tilt angle θ.sub.l on liquid crystals proximate the first substrate, wherein θ.sub.1>5°. The second substrate is substantially reflective and comprises a second alignment layer arranged to impart a second pre-tilt angle Θ.sub.2 on liquid crystals proximate the second substrate, wherein θ.sub.2>5°. The reflective liquid crystal display device further comprises a plurality of pixels defined on the light-modulating layer having a pixel repeat distance x, wherein x≤10 μm. The distance d between inside faces of the first substrate and second substrate satisfies 0.5 μm≤d≤3 μm, and the birefringence of the liquid crystal Δη≥0.20. The holographic projector further comprises a display driver arranged to drive the reflective liquid crystal display device to display a hologram by independently-driving each pixel at a respective modulation level selected from a plurality of modulation levels having a phase modulation value.

HOLOGRAPHIC OPTICAL APPARATUS, HOLOGRAPHIC OPTICAL SYSTEM, AND HOLOGRAPHIC DISPLAY SYSTEM
20210240133 · 2021-08-05 ·

A holographic optical apparatus includes a beam splitting component, a transmission assembly, a focal length modulation component and an optical element. The beam splitting component splits received light into reference light and signal light that are coherent light, and outputs the reference light and the signal light. The focal length modulation component includes a plurality of local length modulation regions with different focal lengths. The optical element includes a recording medium layer with a plurality of recording regions, and each recording region is located in a light-exit path of a focal length modulation region. The transmission assembly is disposed in a light-exit path of the beam splitting component, transmit the reference light to the plurality of recording regions and transmit the signal light to the plurality of focal length modulation regions.

Display device and display method thereof

The present disclosure relates to a display device and a display method thereof. The display device includes: a plurality of sub-pixels each including a light emitting element and a liquid crystal spatial light modulator, wherein the liquid crystal spatial light modulator is located on a light emission side of the light emitting element, and a phase of light emitted by the light emitting element is modulatable after passing through the liquid crystal spatial light modulator; a first control circuit configured to control a light emission intensity and chromaticity of the light emitting element; and a second control circuit configured to control deflection of liquid crystal in the liquid crystal spatial light modulator so as to modulate the phase.

RESONANT LIQUID CRYSTAL DEVICES

A tunable liquid crystal (LC) device includes an LC layer between a pair of reflectors forming an optical cavity. The reflectors include conductive layers for applying an electrical signal to the LC layer. One of the conductive layers may include an array of conductive pixels for spatially selective control of the effective refractive index of the LC layer. The phase delay introduced by the LC layer may be greatly increased or magnified by placing the LC layer into the optical cavity. This enables a substantial reduction of the LC layer thickness, which in its turn enables very tight pitches of the LC pixels, with a reduced inter-pixel crosstalk caused by fringing electric fields, as well as faster switching times. A tight-pitch, fast LC device may be used as a configurable hologram or a spatial light modulator.

HOLOGRAPHIC DISPLAY APPARATUS

A holographic display apparatus includes a light source disposed on a printed circuit board, a display panel diffracting light transferred from the light source, and an optical system disposed between the light source and the display panel. The optical system converts the light incident from the light source into a surface light source.

PROJECTOR WITH PHASE HOLOGRAM MODULATOR

A projection system includes: an illumination source configured to output illumination light; a phase light modulator (PLM) optically coupled to the illumination source, the PLM configured to: receive the illumination light; phase modulate the illumination light while displaying a phase hologram, to produce modulated light; and projection optics coupled to the PLM, the projection optics configured to receive the modulated light and to project an image responsive to the modulated light; wherein both a mean in intensity and a variance in intensity in bright regions of the projected image is greater than the mean intensity and the variance in intensity in dark regions of the projected image.

A DUAL-IMAGE PROJECTION APPARATUS, A HEAD-UP DISPLAY APPARATUS, AND A VEHICLE VISION AUXILIARY SYSTEM
20210199963 · 2021-07-01 · ·

The present application discloses a dual-image projection apparatus. The apparatus includes a light source and a spatial light modulator including a first modulation module and a second nodulation module. Additionally, the apparatus includes a Fourier lens and the spatial light modulator is positioned at a front focal plane of the Fourier lens. The first modulation module modulates light from the light source through the Fourier lens to reproduce a first 2D holographic image and the second modulation module modulates the light through the Fourier lens to reproduce a plurality of second 2D holographic images. The apparatus further includes a first light-diffusing film to display the first 2D holographic image to produce a first virtual image and a plurality of second light-diffusing films to respectively display the plurality of second 2D holographic images sequentially in a rate to produce a 3D virtual image.

EXPOSURE DEVICE FOR RECORDING A HOLOGRAM, METHOD FOR RECORDING A HOLOGRAM, AND METHOD FOR CONTROLLING AN EXPOSURE DEVICE FOR RECORDING A HOLOGRAM
20210191318 · 2021-06-24 ·

An exposure device for recording a hologram. The exposure device includes at least one modulation unit, which is designed to generate a modulation beam representing a reference beam and/or an object beam by impressing a modulation representing at least one holographic element of the hologram onto a laser beam. The exposure device also includes at least one reduction unit, which is designed to generate a modified modulation beam using the modulation beam, the modified modulation beam having a smaller beam diameter than the modulation beam. The exposure device further includes at least one objective lens unit, which is designed to direct the modified modulation beam through an immersion medium onto a recording material in order to record the hologram by exposing the recording material to the modified modulation beam.

HOLOGRAPHIC IMAGE ALIGNMENT
20210191321 · 2021-06-24 ·

A method of holographic projection. The method comprises projecting at least one calibration image using a first colour holographic channel and a second colour holographic channel. Each calibration image comprises at least one light spot. The method comprises performing the following steps for each calibration image in order to determine a plurality of displacements vectors at a respective plurality of different locations on the replay plane. A first step comprises projecting the calibration image onto the replay plane using a first colour holographic channel by displaying a first hologram on a first spatial light modulator and illuminating the first spatial light modulator with light of the first colour. A second step comprises projecting the calibration image onto the replay using a second colour holographic channel by displaying a second hologram on a second spatial light modulator and illuminating the second spatial light modulator with light of the second colour. It may be said that the first and second hologram correspond to the calibration image. A third step comprises determining the displacement vector between the light spot formed by the first colour holographic channel and the light spot formed by the second colour holographic channel. A fourth step comprises pre-processing an image for projection using the second colour holographic channel in accordance with the plurality of determined displacement vectors.

Optical holographic addressing of atomic quantum bits

Atoms and atom-like quantum emitters are promising for quantum sensing, computing, and communications. Lasers and microscopes enable high-fidelity quantum control of the atomic quantum bits (qubits). However, it is challenging to scale up individual quantum control to enough atomic quantum nodes for implementing useful and practical quantum algorithms. Here, we introduce methods and systems to holographically implement large-scale quantum circuits that individually address atomic quantum nodes. These methods enable implementation of quantum circuits over large, multi-dimensional arrays of atomic qubits at rates of thousands to millions of quantum circuit layers per second. The quantum circuit layers are encoded in multiplexed holograms displayed on a slow SLM and retrieved by fast interrogation to produce spatial distributions that operate on the qubit array. This technology can also be used for optically addressing objects such as biological cells and on-chip photonic components for optical tweezers, opto-genetics, optical computing, and optical neural networks.