A head-up display for a vehicle, the head-up display including a picture generating unit arranged to generate a picture on a light receiving surface; and an optical system arranged to image the picture, where the optical system includes an input arranged to receive light of the picture; an output arranged to output light forming an image of the picture; a first mirror and second mirror arranged to guide light from the input to the output along an optical path, where the optical path includes a first optical path from the input to the second mirror including a transmission through the first mirror; and second optical path from the second mirror to the output including a reflection off the first mirror.

A light projection apparatus is provided comprising: a source of light; a switchable grating on a first substrate; and a diffractive optical element. Light is diffracted at least once by the switchable grating and is diffracted at least once by the DOE.

An augmented reality headset may include a reflective holographic combiner to direct light from a light engine into a user's eye while also transmitting light from the environment. The combiner and engine may be arranged to project light fields with different fields of view and resolution to match the visual acuity of the eye. The combiner may be recorded with a series of point to point holograms; one projection point interacts with multiple holograms to project light onto multiple eye box points. The engine may include a laser diode array, a distribution waveguide, scanning mirrors, and layered waveguides that perform pupil expansion and that emit wide beams of light through foveal projection points and narrower beams of light through peripheral projection points. The light engine may include focusing elements to focus the beams such that, once reflected by the holographic combiner, the light is substantially collimated.

An augmented reality headset may include a reflective holographic combiner to direct light from a light engine into a user's eye while also transmitting light from the environment. The combiner and engine may be arranged to project light fields with different fields of view and resolution to match the visual acuity of the eye. The combiner may be recorded with a series of point to point holograms; one projection point interacts with multiple holograms to project light onto multiple eye box points. The engine may include a laser diode array, a distribution waveguide, scanning mirrors, and layered waveguides that perform pupil expansion and that emit wide beams of light through foveal projection points and narrower beams of light through peripheral projection points. The light engine may include focusing elements to focus the beams such that, once reflected by the holographic combiner, the light is substantially collimated.

The disclosed optical lens assemblies may include a deformable element, a structural support element, and a compliant interface material that is disposed between and couples at least a portion of the deformable element and the structural support element. The deformable element may, when deformed, alter an optical property of the optical lens assembly. The compliant interface material may be configured to compensate for a difference between a physical property of the deformable element and the structural support element. Related head-mounted displays and methods are also disclosed.

The disclosed optical lens assemblies may include a pre-strained deformable element that exhibits a non-uniform mechanical strain or stress profile, a structural support element coupled to the pre-strained deformable element, and a deformable medium positioned between the pre-strained deformable element and the structural support element. Related head-mounted displays and methods of fabricating such optical lens assemblies are also disclosed.

A display device according to the present disclosure includes a first optical unit having positive power, a second optical unit including a first diffraction element and having positive power, a third optical unit having positive power, and a fourth optical unit including a second diffraction element and having positive power, and the first to fourth optical units are provided along an optical path of imaging light emitted from an imaging light generating device. The second optical unit further includes a first member provided at one surface side of the first diffraction element, and a second member provided on a side of the first member opposite to a side where the first diffraction element is located, the first member is transmissive and has an elastic modulus of 50 GPa or greater, and the second member is transmissive and has optical power.

A head-mounted display according to the present disclosure includes an imaging light generating device that emits imaging light, and a half mirror that reflects the imaging light and transmits external light. The imaging light is incident on the half mirror as light of a predetermined polarization state, and, with respect to the light of the predetermined polarization state, reflectance of a first polarization by the half mirror is lower than reflectance of a second polarization by the half mirror.

A head mounted display system can include a camera, at least one waveguide, at least one coupling optical element that is configured such that light is coupled into said waveguide and guided therein, and at least one out-coupling element. The at least one out-coupling element can be configured to couple light that is guided within said waveguide out of said waveguide and direct said light to said camera. The at least one coupling element may comprise a diffractive optical element having optical power.

The disclosed optical lens assemblies may include a pre-strained deformable element that exhibits a non-uniform mechanical strain or stress profile, a structural support element coupled to the pre-strained deformable element, and a deformable medium positioned between the pre-strained deformable element and the structural support element. Related head-mounted displays and methods of fabricating such optical lens assemblies are also disclosed.