According to one embodiment, an illumination device, in which a plurality of light guides include a plurality of light guide pairs, each of the plurality of light guide pairs includes a first light guide and a second light guide, the plurality of light guide pairs are connected with their long sides opposed to each other, a plurality of laser light source elements include a plurality of first light source elements arranged to be opposed to a first side surface on a short side of the first light guide of the light guide pair, and a plurality of second light source elements arranged to be opposed to a second side surface of the second light guide of the light guide pair.

Diffraction gratings provide optical elements in head-mounted display systems to, e.g., incouple light into or out-couple light out of a waveguide. These diffraction gratings may be configured to have reduced polarization sensitivity. Such gratings may, for example, incouple or outcouple light of different polarizations with similar level of efficiency. The diffraction gratings and waveguides may include a transmissive layer and a metal layer. The diffraction grating may comprises a blazed grating.

An optical device includes a frame supporting a lightguide, a microdisplay, and a field lens positioned therebetween that directs light from the microdisplay into a top surface of the lightguide. Four optical surfaces of the lightguide include: a curved surface where light from the microdisplay enters a top of the lightguide, curved eye-side and world-side surfaces providing total internal reflection, and a combiner surface. The eye-side surface is used twice. Once in total internal reflection, and a second time as a refractive surface when light is reflected from the combiner surface and is thereby refracted out of the lightguide and directed towards a user's eye. The field lens has a curved first surface oriented toward the microdisplay and a curved second surface oriented toward the top of the lightguide. The combiner surface combines ambient light from a world-side of the lightguide with light from the microdisplay.

In some embodiments, optical systems with a reflector and a lens proximate a light output opening of the reflector provide light output with high spatial uniformity and high efficiency. The reflectors are shaped to provide substantially angularly uniform light output and the lens is configured to transform this angularly uniform light output into spatially uniform light output. The light output may be directed into a spatial light modulator, which modulates the light to project an image.

Display devices include waveguides with in-coupling optical elements that mitigate re-bounce of in-coupled light to improve overall in-coupling efficiency and/or uniformity. A waveguide receives light from a light source and/or projection optics and includes an in-coupling optical element that in-couples the received light to propagate by total internal reflection in a propagation direction within the waveguide. Once in-coupled into the waveguide the light may undergo re-bounce, in which the light reflects off a waveguide surface and, after the reflection, strikes the in-coupling optical element. Upon striking the in-coupling optical element, the light may be partially absorbed and/or out-coupled by the optical element, thereby effectively reducing the amount of in-coupled light propagating through the waveguide. The in-coupling optical element can be truncated or have reduced diffraction efficiency along the propagation direction to reduce the occurrence of light loss due to re-bounce of in-coupled light, resulting in less in-coupled light being prematurely out-coupled and/or absorbed during subsequent interactions with the in-coupling optical element.

According to one embodiment, a display device includes a display panel, a first light guide, and a second light guide. In the first light guide, a first main surface includes a first plane and first grooves between the first plane and a first side surface, a second main surface includes second grooves orthogonal to the first grooves, and a second plane between the second grooves and the first side surface. In the second light guide, a third main surface includes a third plane and third grooves located between the third plane and a fourth side surface, a fourth main surface includes fourth grooves orthogonal to the third grooves, and a fourth plane located between the fourth grooves and the fourth side surface.

An apparatus including a set of three illumination sources disposed in a first plane. Each of the set of three illumination sources is disposed at a position in the first plane offset from others of the set of three illumination sources by 120 degrees measured in polar coordinates. The apparatus also includes a set of three waveguide layers disposed adjacent the set of three illumination sources. Each of the set of three waveguide layers includes an incoupling diffractive element disposed at a lateral position offset by 180 degrees from a corresponding illumination source of the set of three illumination sources.

An image display apparatus including a first waveguide, a second waveguide, a focus tunable lens positioned between the first waveguide and the second waveguide, and a display engine configured to control a focal length of the focus tunable lens and control the display engine to output first light forming the first virtual image and second light forming the second virtual image, wherein at least a portion of the first light is diffracted from the first waveguide and at least a portion of the second light diffracted from the second waveguide is incident on the first waveguide through the focus tunable lens.

An example a head-mounted display device includes a light projector and an eyepiece. The eyepiece is arranged to receive light from the light projector and direct the light to a user during use of the wearable display system. The eyepiece includes a waveguide having an edge positioned to receive light from the display light source module and couple the light into the waveguide. The waveguide includes a first surface and a second surface opposite the first surface. The waveguide includes several different regions, each having different grating structures configured to diffract light according to different sets of grating vectors.

Augmented reality and virtual reality display systems and devices are configured for efficient use of projected light. In some aspects, a display system includes a light projection system and a head-mounted display configured to project light into an eye of the user to display virtual image content. The head-mounted display includes at least one waveguide comprising a plurality of in-coupling regions each configured to receive, from the light projection system, light corresponding to a portion of the user's field of view and to in-couple the light into the waveguide; and a plurality of out-coupling regions configured to out-couple the light out of the waveguide to display the virtual content, wherein each of the out-coupling regions are configured to receive light from different ones of the in-coupling regions. In some implementations, each in-coupling region has a one-to-one correspondence with a unique corresponding out-coupling region.