Augmented reality glasses include near eye displays the include sources of imagewise amplitude modulated light optical coupled to spatial phase modulators or active zone plate modulators and optically coupled to eye coupling optics. The sources of imagewise amplitude modulated light can include emissive 2D display panels or light sources coupled to imagewise amplitude modulators. The eye coupling optics can include volume holographic diffraction gratings.

A directional illuminator for a display apparatus includes a switchable diffuser for tuning a divergence of a light beam illuminating a display panel of the display apparatus. The tunable divergence of the illuminating light beam translates into a tunable exit pupil size at the eyebox of the display apparatus, which may be matched to a pupil size of a user’s eye, thus providing a configurable illumination of the eye pupil. A tiltable reflector in an optical path of the illuminating light beam may be used to shift the location of the exit pupil at the eyebox of the display apparatus.

A pupil-replicating lightguide includes a slab of transparent material, a switchable out-coupling grating for out-coupling portions of image light to propagate towards an eyebox, and a switchable tracking grating for redirecting tracking light carrying an eye image towards an eye tracking camera. One of the two gratings may be turned ON while the other is turned OFF, in a time-sequential manner, allowing the combined use of the pupil-replicating lightguide for carrying image light and eye tracking light.

An illuminator for a display panel includes a slab of transparent material for propagating illuminating light between outer surfaces of the slab, an out-coupler supported by the slab for out-coupling portions of the illuminating light along one of the outer surfaces of the slab, and a tunable microlens array for forming an array of light spots from the out-coupled illuminating light portions downstream of the focusing element for illuminating pixels of the display panel. The array of light spots may be repeated at a distance from the tunable microlens array due to Talbot effect. The display panel may be illuminated in a color-sequential manner, and the tunable microlens array may be used to adjust the focal plane position for each color channel individually.

A pupil-replicating lightguide includes a slab of transparent material for guiding image light in the slab, and an out-coupling structure supported by the slab for out-coupling portions of the image light from the slab. The portions are laterally offset from one another along a path of the image light in the slab. The out-coupling grating structure has a switchable distribution of out-coupling efficiency for redirecting the portions of out-coupled light to a desired location such as a current location of an eye of the viewer determined by an eye tracking system. The out-coupling grating structure may include a plurality of diffraction gratings having different local slant angles of grating fringes.

A pupil-replicating lightguide includes a slab of transparent material for guiding image light in the slab, and an out-coupling structure supported by the slab for out-coupling portions of the image light from the slab. The portions are laterally offset from one another along a path of the image light in the slab. The out-coupling grating structure has a switchable distribution of out-coupling efficiency for redirecting the portions of out-coupled light to a desired location such as a current location of an eye of the viewer determined by an eye tracking system. The out-coupling grating structure may include a plurality of diffraction gratings having different local slant angles of grating fringes.

A field of view of an imaging or ranging device may be increased multiple times by providing a switchable diffraction grating structure upstream of an imaging camera or ranging light source. The switchable diffraction grating changes the angle of propagating of incoming light by a fixed step, enabling the device to switch between several portions of a compound field of view. The switchable diffraction grating structure may be supported by a lightguide that guides the image light or ranging light by a series of reflections from opposed surfaces of the lightguide.

Provided are a display module and augmented reality glasses, which relate to the technical field of augmented reality. The display module includes: a bracket; and a first diffractive waveguide and a second diffractive waveguide that are arranged on the bracket, the first diffractive waveguide and the second diffractive waveguide are configured to correspond to eyes of a user in one-to-one correspondence; the first diffractive waveguide includes a first region that has a projection on the bracket, the first region has a first notch at a side thereof close to the second diffractive waveguide, and the first notch faces towards the second diffractive waveguide. This can reduce the volume of the augmented reality glasses and is beneficial to the miniaturized design of the augmented reality glasses.

Provided are a display module and augmented reality glasses, which relate to the technical field of augmented reality. The display module includes: a bracket; and a first diffractive waveguide and a second diffractive waveguide that are arranged on the bracket, the first diffractive waveguide and the second diffractive waveguide are configured to correspond to eyes of a user in one-to-one correspondence; the first diffractive waveguide includes a first region that has a projection on the bracket, the first region has a first notch at a side thereof close to the second diffractive waveguide, and the first notch faces towards the second diffractive waveguide. This can reduce the volume of the augmented reality glasses and is beneficial to the miniaturized design of the augmented reality glasses.

Cascaded metasurfaces can control the phase, amplitude and polarization of an electromagnetic beam, shaping it in three dimensional configuration not achievable with other methods. Each cascaded metasurface has dielectric or metallic scatterers arranged in a period array. The shape of the scatterers determines the three dimensional configuration of the output beam and is determined with iterative calculations through computational simulations.