Provided are an optical element and an image display apparatus that display an aerial image, in which the total volume of the apparatus is small, a reduction in size can realized, and a scenery can be recognized. The optical element includes: a light guide element including a light guide plate, an incidence diffraction element, and an emission diffraction element, the incidence diffraction element being disposed on a main surface of the light guide plate and the emission diffraction element being disposed on the main surface of the light guide plate; and a positive lens that is disposed at a position overlapping the emission diffraction element in a view from a direction perpendicular to the main surface of the light guide plate, in which the incidence diffraction element diffracts incident light such that the diffracted light is incident into the light guide plate, the emission diffraction element emits light propagating in the light guide plate from the light guide plate, and the positive lens collects the light that is emitted from the light guide plate by the emission diffraction element.

There is disclosed herein a liquid crystal on silicon spatial light modulator, “LCoS SLM”, device arranged for in-plane switching. The LCoS SLM device comprises: a silicon backplane (1501); a transparent substrate (1581); a liquid crystal layer (1571); an electrode structure (1505, 1507) and a reflective component (1561, 1551). The liquid crystal layer (1571) is interposed between the silicon backplane (1501) and the transparent substrate (1581). The electrode structure (1505, 1507) is formed on the silicon backplane (1501) for generating an electric field in the liquid crystal layer (1571). The electric field is substantially parallel to the silicon backplane (1501). The reflective component (1551, 1561) is opposing the transparent substrate (1581).

A prism layer has an uneven surface that includes at least one display region. An interface layer is adjacent to the uneven surface. The interface layer has a difference in refractive index from the prism layer such that a refractive index of a side of an interface between the uneven surface and the interface layer at which the prism layer is located is higher than a refractive index of a side of the interface at which the light interference layer is located. The display region includes inclination elements. The inclination elements adjacent to each other in an array direction contact each other in a plan view facing a plane along which the prism layer expands. The inclination elements include first inclination elements among which the inclination angle increases by the even angles along the array direction.

A holographic optical system and a holographic display method may be efficiently applied when using a spatial light modulator (SLM). A holographic display apparatus includes a spatial light modulator (SLM) configured to reproduce a hologram, and an optical system configured to perform Fourier transform with respect to the hologram of the SLM using a pair of first and second lenses, the first and second lenses being confocal. A Fourier plane which is a display reference image plane is positioned in the same plane space as the second lens.

A method and systems for simultaneous recording of superimposed holographic gratings for augmented reality devices are provided. The method includes: generating a beam by a single light source, directing the beam to a decoherence unit at a predetermined angle, forming at least two recording beams by the decoherence unit by splitting the beam, forming at least two recording channels in the decoherence unit to transmit the at least two recording beams and output them from the decoherence unit, output angles of each of the at least two recording beams being different, the at least two recording beams being non-interfering when leaving the decoherence unit, which is provided in accordance with at least one of: output times, spatial positions, polarization states, or spectral compositions of each of the at least two recording beams, illuminating a recording material layer and one master diffractive optical element/master holographic optical element (master DOE/HOE) comprising at least one preliminary formed diffraction/holographic grating by the at least two non-interfering recording beams, simultaneously forming at least two superimposed holographic gratings from the master DOE/HOE on or in the recording material layer, the formed superimposed holographic gratings having a same surface period, but a different spatial period.

The present disclosure relates to systems and methods for translating optical beams.

A holographic display apparatus includes a backlight unit having a light source configured to emit coherent light, a spatial light modulator configured to diffract incident light from the backlight unit and generate a holographic image, a beam deflector configured to change a traveling direction of the incident light from the backlight unit to change a focal position of the holographic image, an eye-tracking sensor configured to recognize positions of a viewer's eyeballs, and a controller configured to perform, in real time, calibration of the eye-tracking sensor and the beam deflector to focus the holographic image on the recognized positions of the viewer's eyeballs.

The display apparatus of the present disclosure includes an imaging light generating device and an optical system on which imaging light emitted from the imaging light generating device is incident. The optical system includes a first optical unit having positive power, a second optical unit having a positive power and including a first diffraction element, a third optical unit having positive power, and a fourth optical unit having positive power and including a second diffraction element forming an exit pupil, the first optical unit, the second optical unit, the third optical unit, and the fourth optical unit being aligned in order along an optical path of the imaging light. The second diffraction element is constituted of a volume hologram and has, in a cross-sectional view of the volume hologram, interference fringes continuously varying in pitch and inclination thereof from one end toward another end of the second diffraction element.

A system includes a diffractive optical element configured to receive a first beam and a second beam interfering with one another to generate a first interference pattern. The diffractive optical element is also configured to forwardly diffract the first beam and the second beam to output a third beam and a fourth beam. The third beam and the fourth beam interfere with one another to generate a second interference pattern. The system also includes a detector configured to detect the second interference pattern.

Virtual reality (VR) displays are computer displays that present images or video in a manner that simulates a real experience for the viewer. In many cases, VR displays are implemented as head-mounted displays (HMDs) which provide a display in the line of sight of the user. Because current HMDs are composed of a display panel and magnifying lens with a gap therebetween, proper functioning of the HMDs limits their design to a box-like form factor, thereby negatively impacting both comfort and aesthetics. The present disclosure provides a different configuration for a VR display which allows for improved comfort and aesthetics, including specifically at least one coherent light source, at least one pupil replicating waveguide coupled to the at least one coherent light source to receive light therefrom, and at least one spatial light modulator coupled to the at least one pupil replicating waveguide to modulate the light.