A lens assembly, related methods and constituent optical elements are described. The assembly may be used to direct and focus light for various applications. In one instance, the lens assembly is used in conjunction with one or more sources of light such as projected images or video as part of a virtual reality system. The lens assembly includes two or more optical elements arranged to receive light or direct light through different spatial regions of the assembly at different focal powers corresponding to a first user viewing zone and a second user viewing zone. In one instance, the first user viewing zone is a peripheral viewing zone and the second viewing zone is a primary or non-peripheral viewing zone (or vice versa).

An implementation of an optical system for expanding the field of view can include a first optical element and a second optical element. The first optical element can include a first surface and a second surface. The first surface can be configured to reflect a first light beam incident on the first surface at a first incident angle greater than a first predetermined angle, and the second surface can be configured to reflect the reflected first light beam towards a location. The second optical element can include a third surface and a fourth surface. The third surface can be configured to reflect a second light beam incident on the third surface at a second incident angle greater than a second predetermined angle, and the fourth surface can be configured to reflect the reflected second light beam towards the location. Related apparatus, systems, techniques and articles are also described.

A display device, a display method thereof, and a display system. The display device includes at least two display screens; and a light transmission portion, configured to transmit image light emitted by the at least two display screens to a predetermined region. The at least two display screens or the light transmission portion is configured to be movable, so that distances from image planes imaged by the at least two display screens through the light transmission portion to the predetermined region can be adjusted independently.

An optical device includes a first A deflecting member, a first B deflecting member, a first C deflecting member, a second A deflecting member, a second B deflecting member, and a second C deflecting member. Light emitted from an image forming device that enters the first A deflecting member and is emitted toward a pupil of an observer via the first B deflecting member and the first C deflecting member. Light emitted from the image forming device that enters the second A deflecting member is emitted toward the pupil of the observer via the second B deflecting member and the second C deflecting member. A direction of light deflected by the first A deflecting member that is orthogonally projected on a light guide plate is opposite a direction of light deflected by the second A deflecting member that is orthogonally projected on the light guide plate.

A head-mounted device may have displays that provide images. Waveguides may be used in conveying the images to eye boxes. The waveguides may overlap lenses in a glasses frame or other head-mounted support structure. The waveguides and lenses may be transparent. This allows real-world objects to be viewed from the eye boxes. Infrared-light reflectors may overlap the lenses. Gaze tracking system light sources may supply infrared light that reflects from the infrared-light reflectors to the eye boxes to illuminate a user's eyes. Gaze tracking system cameras capture gaze tracking images of the eyes from the eye boxes to track the user's gaze. Fiducials associated with the infrared-light reflectors may be monitored using the gaze tracking system cameras. This allows components such as the gaze tracking system cameras to be calibrated.

An optical device comprises a waveguide plate comprising an entrance pupil grating unit, a left pupil-expanding grating unit, and a right pupil-expanding grating unit. The left and right pupil-expanding grating units are bilaterally symmetric, and left and right exit pupil grating units are bilaterally symmetric. An input light is diffracted by the entrance pupil grating unit to form a first left guided light and a first right guided light, the first left guided light is diffracted by the left pupil-expanding grating unit to form a second left guided light, and the first right guided light is diffracted by the right pupil-expanding grating unit to form a second right guided light. The second left guided light is diffracted by the left pupil-expanding grating unit to form a left output light, and the second right guided light is diffracted by the right pupil-expanding grating unit to form a right output light.

A display has an image projector projecting collimated image illumination along a projection direction, and an optical element having two major surfaces and containing partially reflective surfaces which are internal to the optical element, planar, mutually parallel and overlapping relative to the projection direction. Each ray of the collimated image illumination enters the optical element and is partially reflected by at least two of the partially reflective surfaces so as to be redirected to exit the first major surface along a viewing direction. An alternative implementation, a first reflection from one of the partially reflective surfaces redirects part of the image illumination rays so as to undergo total internal reflection at the major surfaces of the optical element. The rays are then redirected by further reflection from another of the partially reflective surfaces to exit the optical element along the viewing direction.

A virtual image display device including a display panel including a plurality of pixels and configured to display an image, a window disposed on the display panel, and a multi-viewpoint layer provided between the display panel and the window, and including a plurality of lenses.

Provided is a waveguide having a light diffraction unit that diffracts incident light by a multiplex-recorded hologram, in which, in the light diffraction unit, a plurality of holograms having different angles with respect to an incident surface of the waveguide are formed, and when certain parallel light beams are incident, different wavelengths are diffracted by the plurality of holograms.

The disclosed subject matter relates to a light projector module, comprising: a base plate, a light source on one side of the base plate, a micro-electro-mechanical-system (MEMS) scanning assembly on the base plate, and a set of at least one lens mounted on the one side of the base plate between the light source and the MEMS scanning assembly, wherein the MEMS scanning assembly has an arm mounted on and extending from the other side of the base plate, a scanning mirror being movably mounted on the arm and facing the base plate, and wherein a light guide is mounted on the base plate or the arm for directing the at least one light beam from the lens set on the one side to the scanning mirror on the arm extending from said other side of the base plate.