A light modulating device includes a metal layer, a variable resistance material layer above the metal layer and having a plurality of resistance states depending on a voltage applied thereto, and a meta surface layer above the variable resistance material layer and including a nano structure comprising a conductive material and having a sub-wavelength dimension.

A switchable directional display apparatus comprises a spatial light modulator and a backlight comprising a waveguide, two light sources arranged to provide illumination through the edge of the waveguide and a switchable liquid crystal retarder. The light sources and switchable liquid crystal retarder may be controlled to provide a first operating state with a narrow field of view and a second operating state with a wide field of view. Image visibility in wide angle mode of operation may be maximised while visual security level may be maximised in a narrow angle mode of operation, to provide an efficient privacy mode of operation.

A privacy display comprises a spatial light modulator and a compensated switchable liquid crystal retarder arranged between first and second polarisers arranged in series with the spatial light modulator. In a privacy mode of operation, on-axis light from the spatial light modulator is directed without loss, whereas off-axis light has reduced luminance. The visibility of the display to off-axis snoopers is reduced by means of luminance reduction over a wide polar field. In a wide angle mode of operation, the switchable liquid crystal retardance is adjusted so that off-axis luminance is substantially unmodified.

A privacy display comprises a luminance-privacy arrangement and a contrast-privacy arrangement. In a privacy mode of operation, ambient light levels are detected and a visual security level is calculated. At and above a visual security level threshold the luminance-privacy arrangement is operable and below the threshold both the luminance-privacy and contrast-privacy arrangements are operable. Image quality for on-axis users is optimised and high levels of visual security are achieved for off-axis snoopers over a wide range of display illuminance conditions.

A laser processing apparatus includes: a light flux separating-and-combining device configured to polarize and separate a laser light into two polarized light fluxes having polarization orthogonal to each other and emit the two light fluxes with their optical paths matching each other toward different regions of a spatial light modulator, and configured to combine the two polarized light fluxes modulated by the spatial light modulator and emit the two light fluxes toward a condenser lens; and a controller configured to control hologram patterns presented by the spatial light modulator for respective regions of the spatial light modulator irradiated with the two polarized light fluxes such that the laser light is condensed by the condenser lens at two positions different from each other in a thickness direction inside of the wafer and the same as each other in a relative movement direction of the laser light to form modified regions.

The present disclosure relates to a display device and a display method thereof. The display device includes: a plurality of sub-pixels each including a light emitting element and a liquid crystal spatial light modulator, wherein the liquid crystal spatial light modulator is located on a light emission side of the light emitting element, and a phase of light emitted by the light emitting element is modulatable after passing through the liquid crystal spatial light modulator; a first control circuit configured to control a light emission intensity and chromaticity of the light emitting element; and a second control circuit configured to control deflection of liquid crystal in the liquid crystal spatial light modulator so as to modulate the phase.

A spatial light modulator (SLM) comprised of a 2D array of optically-controlled semiconductor nanocavities can have a fast modulation rate, small pixel pitch, low pixel tuning energy, and millions of pixels. Incoherent pump light from a control projector tunes each PhC cavity via the free-carrier dispersion effect, thereby modulating the coherent probe field emitted from the cavity array. The use of high-Q/V semiconductor cavities enables energy-efficient all-optical control and eliminates the need for individual tuning elements, which degrade the performance and limit the size of the optical surface. Using this technique, an SLM with 10.sup.6 pixels, micron-order pixel pitch, and GHz-order refresh rates could be realized with less than 1 W of pump power.

A modular routing node includes a single input port and a plurality of output ports. The modular routing node is arranged to produce a plurality of different deflections and uses small adjustments to compensate for wavelength differences and alignment tolerances in an optical system. An optical device is arranged to receive a multiplex of many optical signals at different wavelengths, to separate the optical signals into at least two groups, and to process at least one of the groups adaptively.

A tunable liquid crystal (LC) device includes an LC layer between a pair of reflectors forming an optical cavity. The reflectors include conductive layers for applying an electrical signal to the LC layer. One of the conductive layers may include an array of conductive pixels for spatially selective control of the effective refractive index of the LC layer. The phase delay introduced by the LC layer may be greatly increased or magnified by placing the LC layer into the optical cavity. This enables a substantial reduction of the LC layer thickness, which in its turn enables very tight pitches of the LC pixels, with a reduced inter-pixel crosstalk caused by fringing electric fields, as well as faster switching times. A tight-pitch, fast LC device may be used as a configurable hologram or a spatial light modulator.

Displays and eyewear devices incorporating displays are disclosed. One display includes a light source, a first display region, and a second display region. The first display region includes a first contiguous array of pixels. The first contiguous array of pixels includes a first group of pixels and a second group of pixels interspersed with the first group of pixels. The first group of pixels is adapted to emit light from the light source in only a first wavelength band and the second group of pixels is adapted to emit light from the light source in only a second wavelength band different from the first wavelength band. The second display region consists essentially of a second contiguous array of pixels. The second contiguous array of pixels is adapted to emit light from the light source in a predetermined wavelength band.