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.

This application relates to a see-through head-mounted display using recorded substrate-guided holographic continuous lens (SGHCL) and a microdisplay with narrow spectral band source or laser illumination. The high diffraction efficiency of the volume SGHCL creates very high luminance of the virtual image.

There is provided a lighting device arranged to produce a controllable light beam for illuminating a scene. The device comprises an addressable spatial light modulator arranged to provide a selectable phase delay distribution to a beam of incident light. The device further comprises Fourier optics arranged to receive phase-modulated light from the spatial light modulator and form a light distribution. The device further comprises projection optics arranged to project the light distribution to form a pattern of illumination as said controllable light beam.

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.

A laser beam (L50) generated by a laser light source (50) is reflected by a light beam scanning device (60), and irradiated onto a hologram recording medium (45). On the hologram recording medium (45), an image (35) of a scatter plate is recorded as a hologram by using reference light that converges on a scanning origin (B). The light beam scanning device (60) bends the laser beam (L50) at the scanning origin (B) and irradiates it onto the hologram recording medium (45). At this time, scanning is carried out by changing the bending mode of the laser beam with time so that the irradiation position of the bent laser beam (L60) on the hologram recording medium (45) changes with time. Regardless of the beam irradiation position, diffracted light (L45) from the hologram recording medium (45) reproduces the same reproduction image (35) of the scatter plate at the same position. An illumination spot in which speckles are reduced is formed on the light receiving surface (R) of an illuminating object (70) by the reproduction image (35) of the hologram.

In the present invention, by providing an apparatus for generating a hologram based on human visual system modeling, including a lens configured to focus light emitted from a three-dimensional (3D) object, a sensor configured to detect the light, an object information obtaining unit configured to obtain object information of the 3D object based on information of the lens and a confusion circle size threshold value corresponding to information of the sensor, and a hologram image generating unit configured to generate a hologram image for the 3D object based on the object information, it is possible to provide a method of generating a hologram based on a human visual system capable of generating image information of a three-dimensional object faster and capable of generating a higher-quality hologram image.

There is provided a holographic display device, which includes a display panel including plural sub-pixels, wherein each sub-pixel includes plural subdivided pixels, and each subdivided pixel has an adjustable light transmittance; a backlight, configured to provide reference light to the display panel; a phase adjustment layer, including plural transparent phase adjustment components, wherein each phase adjustment component is configured to adjust a phase of a light ray transmitted through the phase adjustment component, and the phase adjustment components corresponding to a single sub-pixel have phase adjustment amounts different from each other; and a controller, configured to obtain a target phase of a light ray to be transmitted through each sub-pixel, and determine a target subdivided pixel, which corresponds to the target phase, in each sub-pixel, and further configured to obtain a target intensity of the light ray, and adjust a light transmittance of the target subdivided pixel.

A holographic projector having an optical path is described. The holographic projector comprises a first spatial light modulator arranged to display a first hologram, and a first light source. The first light source is arranged to illuminate the first spatial light modulator with light of a first wavelength such that a first holographic reconstruction corresponding to the first hologram is formed on a replay plane. The holographic projector further comprises a continuous block of transparent material. At least part of the optical path is formed through the continuous block of transparent material. The transparent material has a refractive index greater than air.

An electroluminescent display device includes a substrate including first, second, and third sub-pixel regions; an interlayer insulating layer and a passivation layer each separately disposed at the first, second, and third sub-pixel regions on the substrate; a reflective electrode disposed on the passivation layer of each of the first, second, and third sub-pixel regions; first, second, and third dielectric layers disposed corresponding to the first, second, and third sub-pixel regions, respectively, on the reflective electrode; a first electrode disposed on each of the first, second, and third dielectric layers; an insulating pattern covering an edge of the first electrode; a light-emitting layer disposed on the first electrode and the insulating pattern and substantially all over the substrate including the first, second, and third sub-pixel regions; and a second electrode disposed on the light-emitting layer, wherein the first, second, and third dielectric layers have different thicknesses.

A display may have an array of pixels. Each pixel may have a light-emitting diode such as an organic light-emitting diode or may be formed from other pixel structures such as liquid crystal display pixel structures. The pixels may emit light such as red, green, and blue light. An angle-of-view adjustment layer may overlap the array of pixels. During operation, light from the pixels passes through the angle-of-view adjustment layer to a user. The viewing angle for the user is enhanced as the angular spread of the emitted light from the pixels is enhanced by the angle-of-view adjustment layer. The angle-of-view adjustment layer may be formed from holographic structures recorded by applying laser beams to a photosensitive layer or may be formed from a metasurface that is created by patterning nanostructures on the display using printing, photolithography, or other patterning techniques.