A holographic display apparatus capable of providing an expanded viewing window and a display method are provided. The holographic display apparatus includes an image processor configured to provide computer generated hologram (CGH) data to a spatial light modulator, wherein the image processor is further configured to generate a hologram data array comprising information of the holographic image to be reproduced at the first resolution or a resolution less than the first resolution, perform an off-axis phase computation on the hologram data array at the second resolution, and then, generate the CHG data at the first resolution.

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 display and a method, performed by the holographic display, of forming a holographic image are disclosed. The holographic display includes an electrically addressable spatial light modulator (EASLM); a diffractive optical element (DOE) mask array arranged on the EASLM; and a controller configured to operate the holographic display to form a hologram image, wherein the controller is further configured to address the EASLM to backlight the DOE mask array required to form a set of hologram image voxels by turning on a corresponding EASLM pixel.

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 co-located imaging and display pixel includes an image pixel having a photosensitive element and a display pixel co-located with the image pixel. An optical transformation engine is coupled between the image pixel and the display pixel. The optical transformation engine is configured to modulate an amplitude of display light emitted by the display pixel in response to receiving an imaging signal generated by the photosensitive element of the image pixel.

Disclosed are an active complex spatial light modulation method and apparatus for an ultra-low noise holographic display. The active complex spatial light modulation apparatus includes a substrate and a petal antenna including three petal patterns arranged on the substrate, dividing a complex plane into three phase sections, and modulating the input light into three-phase amplitude values corresponding to the phase sections. The petal antenna may have a point symmetry shape based on the center point of the petal antenna.

There is provided a spatial light modulator arranged to display a light modulation pattern comprising a hologram. The spatial light modulator comprises a liquid crystal on silicon spatial light modulator having a plurality of pixels. The hologram has a plurality of pixels. The spatial light modulator comprises a silicon backplane. Each pixel of the spatial light modulator comprises a light-modulating element and a respective pixel circuit. Each pixel circuit is embedded in the silicon backplane. Each pixel circuit is arranged to drive the corresponding light-modulating element. Each pixel circuit is further arranged to combine a received pixel value of the hologram with a corresponding pixel value of the light processing function such that the light modulation pattern further comprises the light processing function. The light processing function comprises a lens function and/or a grating function.

Embodiments of the present disclosure provide a holographic display device. The holographic display device includes a spatial light modulator and a light source unit. The light source unit is provided on the light entry side of the spatial light modulator and configured to providing read-out light to the spatial light modulator. The spatial light modulator includes at least one loading portion for receiving a write-in signal, which comprises a plurality of pixel units arranged in a matrix form, and the light exit surface of at least a part of which is a first cambered surface protruding in a direction away from the light source unit.

Various examples of out-of-plane multicolor waveguide holography systems, methods of manufacture, and methods of use are described herein. In some examples, a multicolor waveguide holography system includes a planar waveguide to convey optical radiation between a grating coupler and a metasurface hologram. The grating coupler may be configured to couple out-of-plane optical radiation of three different color incident at three different angles into the planar waveguide. The combined multicolor optical radiation may be conveyed by the waveguide to the metasurface hologram. The metasurface hologram may diffractively decouple the three colors of optical radiation for off-plane propagation to form a multicolor holographic image in free space.

A liquid crystal display device and corresponding method to display a hologram is described. A grey level value for each pixel of a hologram is received and a pixel voltage based on grey level for each pixel of the hologram is determined. The pixels of the display device are driven in accordance with a first representation of the pixel voltages during at least one first drive event. The pixels of the display device are driven in accordance a second representation of the pixel voltages during at least one second drive event after the at least one first drive event. The first representation may be an n-bit representation and the second representation may be a m-bit representation and n<m. The at least one first drive event may be shorter in duration than the at least one second drive event.