An illumination apparatus that illuminates an illumination zone having a first direction and a second direction crossing the first direction is provided with a light source to emit a coherent light beam, and a diffraction optical device to diffract the coherent light beam incident from the light source. The diffraction optical device diffracts the incident coherent light beam so that a width of the illumination zone in the second direction gradually becomes wider along the first direction of the illumination zone from a nearer side to the diffraction optical device.

A holographic image display device according to one embodiment comprises: an image display unit on which a holographic image is displayed; and a spatial impression providing unit which forms a space surrounding the holographic image, and includes a transparent color material such that the space looks colored and the holographic image can be recognized from the outside.

Methods, apparatus, devices, and systems for displaying three-dimensional objects by individually diffracting different colors of light are provided. In one aspect, a system includes a display having a plurality of display elements and an optical device configured to diffract a plurality of different colors of light to the display. The optical device is configured such that, when the plurality of different colors of light is incident on the optical device, the optical device separates light of individual colors of the different colors while suppressing crosstalk between the different colors.

Methods, apparatus, devices, and systems for reconstructing three-dimensional objects with display zero order light suppression are provided. In one aspect, a method includes illuminating a display with light, a portion of the light illuminating display elements of the display, and modulating the display elements of the display with a hologram corresponding to holographic data to diffract the portion of the light to form a holographic scene corresponding to the holographic data, and to suppress display zero order light in the holographic scene. The display zero order light can include reflected light from the display.

An illumination apparatus that illuminates an illumination zone having a first direction and a second direction crossing the first direction is provided with a light source to emit a coherent light beam, and a diffraction optical device to diffract the coherent light beam incident from the light source. The diffraction optical device diffracts the incident coherent light beam so that a width of the illumination zone in the second direction gradually becomes wider along the first direction of the illumination zone from a nearer side to the diffraction optical device.

A system for displaying three dimensional (3D) images. The system includes a 3D display operating in a first state to display a 3D image by outputting light into a viewing space and operating in a second state in which the 3D image is not displayed. The system further includes a screen element positioned between the 3D display and the viewing space. The screen element reflects light from the viewing space to appear opaque to a viewer in the viewing space when the 3D display operates in the second state. The screen element transmits the light output by the 3D display, whereby the 3D display image is perceivable by the viewer in the viewing space. The screen element includes a sheet of mesh or netting material that transmits light output by the 3D display through its pores or openings and may be a planar sheet of scrim or tulle.

A display apparatus includes a coherent light source, a display unit, a light-diffusing element, and at least one optical element. The coherent light source is configured to provide coherent light beams. The display unit is configured to form a three-dimensional image beam based on interference of the coherent light beams, wherein the three-dimensional image beam is imaged on an intermediate imaging surface after passing through the display unit. The light-diffusing element is located on the intermediate imaging surface, wherein a diffusion angle of the three-dimensional image beam is sequentially changed by passing through the light-diffusing element. The at least one optical element is located on a transmission path of the three-dimensional image beam from the light-diffusing element, and is configured to project the three-dimensional image light beam passing through the display unit out of the display apparatus to display a three-dimensional image.

A holographic display system for a motor vehicle includes a light source for generating a beam of coherent light and a spatial light modulator (SLM) having a two-dimensional pixel array. The two-dimensional pixel array modulates the beam of coherent light for generating a plurality of subframes, with each subframe being associated with one of a plurality of partial fields of view. The system further includes a scanner for directing the subframes onto associated sections of a display surface. The system further includes a computer having a memory including instructions, such that a processor is programmed to control the two-dimensional pixel array of the SLM for generating the subframes. The processor is further programmed to control the scanner for directing the subframes onto associated sections of the display surface and displaying a reconstructed image within a full field of view, which includes each of the partial fields of view.

A system for making a holographic medium for use in generating light patterns for eye tracking includes a light source configured to provide light and a beam splitter configured to separate the light into a first portion of the light and a second portion of the light that is spatially separated from the first portion of the light. The system also includes a first set of optical elements configured to transmit the first portion of the light for providing a first wide-field beam onto an optically recordable medium and one or more diffractive optical elements configured to receive the second portion of the light and project a plurality of separate light patterns onto the optically recordable medium for forming the holographic medium.

Methods, apparatus, devices, and systems for displaying three-dimensional objects by individually diffracting different colors of light are provided. In one aspect, an optically diffractive device includes: first and second diffractive components and a color-selective polarizer therebetween. The first diffractive component is configured to diffract a first color of light in a first polarization state incident at a first incident angle with a first diffraction efficiency at a first diffracted angle, and diffract a second color of light in a second polarization state with a diffraction efficiency substantially less than the first diffraction efficiency. The color-selective polarizer is configured to rotate the second polarization state of the second color of light to the first polarization state. The second diffractive component is configured to diffract the second color of light in the first polarization state with a second diffraction efficiency at a second diffracted angle substantially identical to the first diffracted angle.