There is disclosed herein a display device comprising a picture generating unit, a waveguide pupil expander and a viewer-tracking system. The picture generating unit comprises a first display channel, a second display channel and a controller. The first display channel is arranged to output first spatially-modulated light of a first colour. The first spatially-modulated light corresponds to a first picture. The second display channel is arranged to output second spatially-modulated light of a second colour. The second spatially-modulated light corresponding to a second picture. The controller is arranged to drive the first display channel and second display channel. The waveguide pupil expander comprises a pair of parallel reflective surfaces. The waveguide pupil expander defines an input port and a viewing window. The input port is arranged to receive the first spatially-modulated light and the second spatially-modulated light. The viewing window is an area or volume within which a viewer may view the first picture and the second picture. The pair of parallel reflective surfaces is arranged to guide the first spatially-modulated light and the second spatially-modulated light from the input port to the viewing window by a series of internal reflections. The reflectivity of a first reflective surface of the pair of parallel reflective surfaces is provided by a graded coating. The graded coating is partially transmissive to light of the first colour and light of the second colour. The transmissivity of the graded coating is non-achromatic. The viewer-tracking system is arranged to determine a viewing position within the viewing window. The controller is arranged to maintain as substantially constant the colour balance of the first and second picture as seen from the viewing position based on the viewing position determined by the viewer-tracking system.

Apparatus and methods for 3D-Scanless Holographic Optogenetics with Temporal focusing (3D-SHOT), which allows precise, simultaneous photo-activation of arbitrary sets of neurons anywhere within the addressable volume of the microscope. Soma-targeted (ST) optogenetic tools, ST-ChroME and IRES-ST-eGtACR1, optimized for multiphoton activation and suppression are also provided. The methods use point-cloud holography to place multiple copies of a temporally focused disc matching the dimensions of a designated neuron's cell body. Experiments in cultured cells, brain slices, and in living mice demonstrate single-neuron spatial resolution even when optically targeting randomly distributed groups of neurons in 3D.

A method of manufacturing an optical element including, a first step of, after affixing a hologram forming material to a glass substrate having a marking portion, performing interference exposure on the hologram forming material, thereby forming a hologram layer at the glass substrate, and a second step of affixing the hologram layer peeled off from the glass substrate to a plastic substrate having a first alignment mark, wherein in the second step, the first alignment mark on the plastic substrate, and a second alignment mark formed at a position corresponding to the marking portion in the hologram layer during the interference exposure are used to implement positioning of the plastic substrate and the hologram layer.

Provided is a technology for implementing an AR optical waveguide display capable of showing a hologram image by means of a small and simple system configuration by using an HOE. A holographic display according to an embodiment of the present invention comprises: a light source module for emitting a beam; an optical waveguide through which the emitted beam is incident and propagated; a plurality of holographic optical elements (HOES) for propagating the beam incident to the optical waveguide inside the optical waveguide while totally reflecting the beam; and a modulator for reproducing a holographic image through the progressing beam and propagating the beam to the inside of the optical waveguide while totally reflecting the beam. Accordingly, it is possible to implement, as a small and simple system, an optical waveguide display showing an AR hologram by using an optical waveguide and an HOE.

Provided is a holographic image processing apparatus including a memory configured to store at least one instruction, and a processor configured to execute the at least one instruction stored in the memory to generate a corrected holographic image by correcting an original holographic image captured by a holographic camera based on a neural network configured to learn hologram correction in advance.

A method and apparatus for processing hologram image data capable of optimizing image quality of a hologram image are provided. The image processing method includes receiving input image data, reading a header included at a predetermined location in the input image data, and generating hologram data configured to display a hologram image by performing a Fourier calculation and pixel encoding on the input image data based on at least one parameter recorded in the header, wherein the at least one parameter recorded in the header includes at least one of depth information, scale information, and gamma information.

An optical member utilizing light from a point light source is enabled to visually perceive a reproduced optical image with a desired color. An optical modulation device includes an optical member having a light control part to reflect or absorb light in a predetermined wavelength and to pass through light in other than the predetermined wavelength in light in at least a visible light band, in accordance with a reproduction reference image for reproducing an original image, and a light transmissive part to pass through light in at least the visible light range including the predetermined wavelength.

Projection displays include a highlight projector and a main projector. Highlights projected by the highlight projector boost luminance in highlight areas of a base image projected by the main projector. Various highlight projectors including steerable beams, holographic projectors and spatial light modulators are described.

A display for displaying a wide Field of View (FoV) scene including a holographic image within the scene, including a first Spatial Light Modulator (SLM) and an optical system for producing a first holographic image at a center of a displayed scene, and a second image display for producing at least a first additional image adjacent to the first holographic image. In some embodiments an augmented reality display is used for the displaying of the first holographic image at the center of a field of view and the second image adjacent to the first holographic image. In some embodiments a virtual reality display is used for the displaying of the first holographic image near the center of a field of view and the second image adjacent to the first holographic image. Related apparatus and methods are also described.

Authentication systems, devices, and methods are provided, which may use a scanner configured to capture an image of an authentication pattern in a predetermined target area; and a hologram generator configured to project a holographic target onto free space in the target area. Moreover, there may be provided a controller configured to process the image and output a determination of whether the authentication pattern meets a predetermined criterion.