An image display device projecting an image to a user includes: an image generation unit that generates image light; a projection optical unit that projects the image light generated by the image generation unit; an image light duplication unit that duplicates and emits the image light projected by the projection optical unit; and a light-guiding unit that projects the image light duplicated by the image light duplication unit to a user, in which the projection optical unit includes at least one projection lens, and in which an interval at which the image light duplication unit duplicates the image light is smaller than an outer diameter of the projection lens.

A backlight module including a light guide plate, a light source, a prism sheet and a light absorbing sheet is provided. The light guide plate has a light incident surface, a light emitting surface connected to the light incident surface and a bottom surface opposite to the light emitting surface. At least one of the light emitting surface and the bottom surface of the light guide plate is disposed with a plurality of micro lens structures. The light source is disposed on a side of the light incident surface of the light guide plate. The prism sheet is overlapped with the light emitting surface of the light guide plate and has a plurality of prism structures facing the light emitting surface with an extending direction parallel to the light incident surface. The light absorbing sheet is disposed on a side of the bottom surface of the light guide plate.

Disclosed is a display apparatus capable of improving a sound quality through an accurate sound transmission, wherein the display apparatus may include a backlight module connected with a rear surface of a display panel, a rear structure for surrounding the backlight module, and a vibration generating device for vibrating the display panel through the backlight module, wherein the vibration generating device is fixed to the rear structure.

An optical device includes a liquid-crystal variable retarder. An exit-pupil expander is optically coupled to the liquid-crystal variable retarder, the exit-pupil expander includes: at least one optical input feature that receives reference light from a reference light source; and one or more optical coupling elements coupled to receive the reference light from the reference light source and expand the reference light to one or more spatially-separated regions of the liquid-crystal variable retarder.

Apparatuses and systems including curved optical waveguides, and methods for use include an output-grating of a curved waveguide that includes a spatially modulated grating period configured to cause, for each beam of light corresponding to an image coupled into a bulk-substrate of the curved waveguide by an input-grating, corresponding rays of light output from different locations of the output-grating to be substantially collimated. Adaptive optics of a display engine compensate for aberrations that vary over a field-of-view associated with light corresponding to the image out-coupled by the output-grating. Further, a curved portion of the curved waveguide is designed to keep internally reflected light below a critical angle to prevent inadvertent out-coupling thereof. Further, curved surfaces of the curved waveguide can include polynomial surfaces to compensate for lateral color errors and distortion.

A light guide plate, a backlight module and a display device are disclosed. The light guide plate includes: a first optical path control layer, a second optical path control layer, and a light guide layer that are sequentially stacked. A plurality of prism structures are provided on a side of the first optical path control layer distal to the second optical path control layer. The first optical path control layer, the second optical path control layer, and the light guide layer all extend in a first direction. The first optical path control layer is configured to deflect the light that enters the first optical path control layer from the light guide layer through the second optical path control layer, so that the deflected light passes through the second optical path control layer and is emitted from the light exit surface of the light guide layer.

A display device includes: a display panel; a housing that comprises a front face in which the display panel is disposed; a light source unit that is disposed on an inner surface of the housing, and comprises a light source and an optical lens covering the light source; an attenuating plate that is disposed between the light source unit and the display panel, and attenuates an intensity of light irradiated from the light source unit, the light passing through the attenuating plate toward the display panel; and a reflection plate that reflects the light having passed through the attenuating plate toward the display panel.

A diffractive multiview backlight and a multiview display employ an array of diffractive multibeam elements including a plurality of diffraction gratings configured to provide a plurality of light beams having different principal angular directions corresponding to different view directions of the multiview display. The display includes multiview pixels that include sub-pixels. A size of the diffractive multibeam element of the array is comparable to a size of a sub-pixel in a multiview pixel of the multiview display.

A hologram reproducing apparatus is provided that includes a display configured to emit a write beam corresponding to a hologram pattern, a spatial light modulator (SLM) configured to write the hologram pattern according to the write beam and modulate the reproduction beam into a plurality of diffraction beams corresponding to the hologram pattern if a reproduction beam is incident, a light guide plate disposed in a front surface of the SLM, and configured to guide the reproduction beam toward the SLM, a filter configured to filter the plurality of diffraction beams, a lens configured to focus the plurality of diffraction beams filtered through the filter, and a plurality of optical fibers arranged in order to dispose at least one optical fiber to correspond to each of a plurality of pixels included in the display, and configured to transmit the write beam to the SLM.

A pupil replication waveguide for a projector display includes a slab of transparent material for propagating display light in the slab via total internal reflection. A diffraction grating is supported by the slab. The diffraction grating includes a plurality of tapered slanted fringes in a substrate for out-coupling the display light from the slab by diffraction into a blazed diffraction order. A greater portion of the display light is out-coupled into the blazed diffraction order, and a smaller portion of the display light is out-coupled into a non-blazed diffraction order. The tapered fringes result in the duty cycle of the diffraction grating varying along the thickness direction of the diffraction grating, to facilitate suppressing the portion of the display light out-coupled into the non-blazed diffraction order.