Adaptive image-replicating display

1 . A system comprising:

a tracker;

an image-replicating display configured to emit light rays forming a spatially-invariant angular light field from each of a plurality of positions on an exit aperture of the image-replicating display; and

at least one processor configured to:

determine a relative position of an interpupillary midpoint between a first eye and a second eye of a user with respect to an image plane of the image-replicating display, using the tracker;

generate or retrieve an image to be displayed based on the relative position of the interpupillary midpoint with respect to the image plane, wherein the image corresponds to a perspective projection having a view origin at the interpupillary midpoint and aligned with an optical axis of the image-replicating display; and

display the image via the image-replicating display.

2 . The system of claim 1 , wherein the at least one processor is configured to:

determine pixels of the image whose emitted light rays would not be directed toward any of the first eye and the second eye of the user during display of the image, based on the relative position of the interpupillary midpoint with respect to the image plane or a relative position of a head of the user with respect to the image plane, and dimensions of the exit aperture of the image-replicating display; and

when generating the image, omit generating pixel values corresponding to the determined pixels.

3 . The system of claim 1 , wherein the image-replicating display comprises an array of microlenses, wherein each microlens is disposed on an optical path of light rays emitted from a respective position on the exit aperture.

4 . The system of claim 3 , wherein the at least one processor is configured to:

determine an average virtual depth at which at least one virtual object is to be presented; and

control focal lengths of microlenses in at least a portion of the array, based on the average virtual depth.

5 . The system of claim 4 , wherein when determining the average virtual depth, the at least one processor is configured to apply different weights to at least one of: different virtual objects, different portions of the at least one virtual object, based on at least one of: respective positions of the different virtual objects in the image plane, respective positions of the different portions of the at least one virtual object in the image plane.

6 . The system of claim 3 , wherein the at least one processor is configured to:

determine gaze directions of the first eye and the second eye, using the tracker;

determine a virtual object or a portion of the virtual object at which the user is looking, based on the gaze directions of the first eye and the second eye; and

control focal lengths of microlenses in at least a portion of the array, based on a virtual depth at which the virtual object or the portion of the virtual object is to be presented.

7 . The system of claim 3 , wherein the at least one processor is configured to:

determine a virtual depth at which at least one virtual object is to be presented;

determine a portion of the exit aperture of the image-replicating display whose emitted light rays are directed toward the first eye and the second eye of the user, based on the relative position of the interpupillary midpoint with respect to the image plane or a relative position of a head of the user with respect to the image plane; and

control focal lengths of microlenses disposed on respective optical paths of positions on said portion of the exit aperture, based on the virtual depth at which the at least one virtual object is to be presented.

8 . The system of claim 3 , wherein the microlenses in the array comprise static microlenses having fixed focal lengths.

9 . The system of claim 1 , wherein the image-replicating display is transparent.

10 . The system of claim 1 , wherein the image-replicating display comprises:

a display unit; and

a transparent image-replicating waveguide optically coupled to the display unit, the transparent image-replicating waveguide being disposed on an optical path of a real-world light field from a real-world environment,

wherein the transparent image-replicating waveguide is configured to guide the light rays produced by the display unit along a propagation path within the transparent image-replicating waveguide and to emit the light rays along the optical path of the real-world light field.

11 . A method comprising:

determining a relative position of an interpupillary midpoint between a first eye and a second eye of a user with respect to an image plane of an image-replicating display, using a tracker;

generating or retrieving an image to be displayed based on the relative position of the interpupillary midpoint with respect to the image plane, wherein the image corresponds to a perspective projection having a view origin at the interpupillary midpoint and aligned with an optical axis of the image-replicating display; and

displaying the image via the image-replicating display, wherein the image-replicating display is configured to emit light rays forming a spatially-invariant angular light field from each of a plurality of positions on an exit aperture of the image-replicating display.

12 . The method of claim 11 , further comprising:

determining pixels of the image whose emitted light rays would not be directed toward any of the first eye and the second eye of the user during display of the image, based on the relative position of the interpupillary midpoint with respect to the image plane or a relative position of a head of the user with respect to the image plane, and dimensions of the exit aperture of the image-replicating display; and

when generating the image, omitting generating pixel values corresponding to the determined pixels.

13 . The method of claim 11 , wherein the image-replicating display comprises an array of microlenses, wherein each microlens is disposed on an optical path of light rays emitted from a respective position on the exit aperture.

14 . The method of claim 13 , further comprising:

determining an average virtual depth at which at least one virtual object is to be presented; and

controlling focal lengths of microlenses in at least a portion of the array, based on the average virtual depth.

15 . The method of claim 14 , wherein determining the average virtual depth comprises applying different weights to at least one of: different virtual objects, different portions of the at least one virtual object, based on at least one of: respective positions of the different virtual objects in the image plane, respective positions of the different portions of the at least one virtual object in the image plane.

16 . The method of claim 13 , further comprising:

determining gaze directions of the first eye and the second eye, using the tracker;

determining a virtual object or a portion of the virtual object at which the user is looking, based on the gaze directions of the first eye and the second eye; and

controlling focal lengths of microlenses in at least a portion of the array, based on a virtual depth at which the virtual object or the portion of the virtual object is to be presented.

17 . The method of claim 13 , further comprising:

determining a virtual depth at which at least one virtual object is to be presented;

determining a portion of the exit aperture of the image-replicating display whose emitted light rays are directed toward the first eye and the second eye of the user, based on the relative position of the interpupillary midpoint with respect to the image plane or a relative position of a head of the user with respect to the image plane; and

controlling focal lengths of microlenses disposed on respective optical paths of positions on said portion of the exit aperture, based on the virtual depth at which the at least one virtual object is to be presented.