Virtual and augmented reality display systems with emissive micro-displays
A wearable display system includes one or more emissive micro-displays, e.g., micro-LED displays. The micro-displays may be monochrome micro-displays or full-color micro-displays. The micro-displays may include arrays of light emitters. Light collimators may be utilized to narrow the angular emission profile of light emitted by the light emitters. Where a plurality of emissive micro-displays is utilized, the micro-displays may be positioned at different sides of an optical combiner, e.g., an X-cube prism which receives light rays from different micro-displays and outputs the light rays from the same face of the cube. The optical combiner directs the light to projection optics, which outputs the light to an eyepiece that relays the light to a user's eye. The eyepiece may output the light to the user's eye with different amounts of wavefront divergence, to place virtual content on different depth planes.
1 . A head-mounted display system comprising:
an emissive micro-display comprising an array of light emitters corresponding to pixels, wherein the array of light emitters is configured to output image light that defines images, wherein the array of light emitters includes a plurality of groups of the light emitters, and wherein each group of the light emitters includes respective first and second light emitters;
an eyepiece configured to receive the image light from the emissive micro-display and to direct the image light to an eye of a user; and
an array of light collimators proximate the array of light emitters, wherein each of the groups of light emitters is associated with a single light collimator of the array of light collimators that is configured to receive and to concentrate the image light that is output by the associated group of light emitters, wherein a first light collimator of the array of light collimators is associated with a first group of the light emitters, wherein a second light collimator of the array of light collimators is associated with a second group of the light emitters, and wherein the first and second light collimators are arranged such that:
the image light that is output by the first light emitter of the first group and the first light emitter of the second group is directed to a same first output area, and
the image light that is output by the second light emitter of the first group and the second light emitter of the second group is directed to a same second light output area that is offset from the first output area.
2 . The head-mounted display system of claim 1 , wherein the emissive micro-display is a micro-LED display.
3 . The head-mounted display system of claim 1 , wherein the light collimators comprise micro-lenses.
4 . The head-mounted display system of claim 1 , wherein the light collimators comprise nano-lenses.
5 . The head-mounted display system of claim 1 , wherein the light collimators comprise reflective wells.
6 . The head-mounted display system of claim 1 , wherein the light collimators comprise metasurfaces.
7 . The head-mounted display system of claim 1 , wherein the light collimators comprise liquid crystal gratings.
8 . The head-mounted display system of claim 1 , further comprising projection optics configured to converge light from the emissive micro-display onto the eyepiece.
9 . The head-mounted display system of claim 1 , wherein individual ones of the light emitters are configured to emit light of one of a plurality of component colors, wherein the eyepiece includes a waveguide assembly that comprises a plurality of sets of waveguides, wherein each set of waveguides comprises a dedicated waveguide for each component color, wherein each set of waveguides comprises out-coupling optical elements configured to output light with wavefront divergence corresponding to a common depth plane, wherein different sets of waveguides output light with different amounts of wavefront divergence corresponding to different depth planes.
10 . The head-mounted display system of claim 1 , further comprising first and second variable focus lens elements, wherein the eyepiece is between the first and second variable focus lens elements, wherein the first variable focus lens element is configured to modify a wavefront divergence of light outputted by the eyepiece toward the eye, and wherein the second variable focus lens element is configured to modify a wavefront divergence of light from an external world.
11 . The head-mounted display system of claim 1 , wherein the eyepiece includes a waveguide assembly comprising one or more waveguides, each waveguide comprising:
an in-coupling optical element configured to in-couple light from the micro-display into the waveguide; and
an out-coupling optical element configured to out-couple in-coupled light out of the waveguide,
wherein the waveguide assembly is configured to output the out-coupled light with variable amounts of wavefront divergence corresponding to a plurality of depth planes.
12 . The head-mounted display system of claim 11 , wherein the waveguide assembly comprises a stack of waveguides.
13 . The head-mounted display system of claim 12 , further comprising a color filter between two neighboring waveguides of the stack of waveguides, wherein a first of the neighboring waveguides precedes a second of the neighboring waveguides in a light path extending from the emissive micro-display, wherein the color filter is configured to selectively absorb light of a wavelength corresponding to a wavelength of light configured to be in-coupled by the in-coupling optical element of the first of the neighboring waveguides.
14 . The head-mounted display system of claim 13 , further comprising:
a third waveguide following the second of the neighboring waveguides in the light path; and
an other color filter configured to selectively absorb light of a wavelength corresponding to a wavelength of light configured to be in-coupled by the in-coupling optical element of the second of the neighboring waveguides.
15 . The head-mounted display system of claim 12 , further comprising absorptive color filters on major surfaces of at least some of the waveguides, wherein the absorptive color filters on major surfaces of the waveguides are configured to absorb light of wavelengths in-coupled into a corresponding waveguide.
16 . The head-mounted display system of claim 12 , wherein the in-coupling optical elements are configured to in-couple light with the in-coupled light propagating generally in a propagation direction through an associated waveguide, wherein the in-coupling optical elements occupy an area having a width parallel to the propagation direction and a length along an axis crossing the propagation direction, wherein the length is greater than the width.
17 . The head-mounted display system of claim 1 , wherein the emissive micro-display is a full-color emissive micro-display comprising the array of light emitters that are each configured to emit light of one of a plurality of component colors.
18 . The head-mounted display system of claim 1 , wherein the first light emitter of the first group and the first light emitter of the second group emit image light of a first color, and wherein second light emitter of the first group and the second light emitter of the second group emit image light of a second color that is different than the first color.