Display systems and methods for determining registration between a display and a user's eyes
A display system may include a head-mounted display (HMD) for rendering a three-dimensional virtual object which appears to be located in an ambient environment of a user of the display. One or more eyes of the user may not be in desired positions, relative to the HMD, to receive, or register, image information outputted by the HMD and/or to view an external environment. For example, the HMD-to-eye alignment may vary for different users and/or may change over time (e.g., as the HMD is displaced). The display system may determine a relative position or alignment between the HMD and the user's eyes. Based on the relative positions, the wearable device may determine if it is properly fitted to the user, may provide feedback on the quality of the fit to the user, and/or may take actions to reduce or minimize effects of any misalignment.
1 . A display system configured to project light to an eye of a user to display virtual image content, the display system comprising:
a frame configured to be supported on a head of the user;
a display disposed on the frame, the display configured to project light into the eye to display the virtual image content with different amounts of wavefront divergence to present the virtual image content appearing to be located at different depths while an external environment is viewable by the eye;
one or more eye-tracking cameras configured to image the eye; and
processing electronics in communication with the display and the one or more eye-tracking cameras, the processing electronics configured to:
determine a display registration volume relative to the display such that the virtual image content is received by the eye while the eye is situated within the display registration volume;
determine a housing registration volume relative to the frame such that an external field of view of the external environment proximal to the display is viewable by the eye while the eye is situated within the housing registration volume;
determine a combined registration volume that includes a plurality of points that are included in both the display registration volume and the housing registration volume;
determine a three-dimensional (3D) position of the eye based on one or more images of the eye obtained with the one or more eye-tracking cameras;
determine whether the position of the eye is within the combined registration volume; and
control operation of the display based on determining whether the position of the eye is within the combined registration volume, wherein controlling the operation of the display includes providing, to the user, a notification of misregistration based at least partly on determining that the eye is not within the combined registration volume.
2 . The display system of claim 1 , wherein the combined registration volume includes all of the points that are included in both the display registration volume and the housing registration volume.
3 . The display system of claim 1 , wherein the housing registration volume is defined relative to one or more housing openings in the frame.
4 . The display system of claim 3 , wherein the housing registration volume has a cone-like shape with a base defined by the shape and size of the one or more housing openings.
5 . The display system of claim 1 , wherein the position of the eye is a center of rotation of the eye.
6 . The display system of claim 1 , wherein the display registration volume has a frustum shape.
7 . The display system of claim 1 , wherein the notification of misregistration is provided to the user based on determining that the position of the eye is more than a threshold distance outside of the combined registration volume.
8 . The display system of claim 1 , wherein the display registration volume is defined based at least partly on a type of application that is running on the display system.
9 . Non-transitory computer-readable storage media storing instructions which, when executed by at least one processor, instruct the at least one processor to perform operations for controlling a wearable display configured to project light to an eye of a user to display virtual image content, the operations comprising:
determining a display registration volume relative to the display such that the virtual image content is received by the eye while the eye is situated within the display registration volume;
determining a housing registration volume relative to the frame such that an external field of view of an external environment proximal to the display is viewable by the eye while the eye is situated within the housing registration volume;
determining a combined registration volume that includes a plurality of points that are included in both the display registration volume and the housing registration volume;
determining a three-dimensional (3D) position of the eye based on one or more images of the eye obtained with one or more eye-tracking cameras configured to image the eye while the display is being worn by the user;
determining whether the position of the eye is within the combined registration volume; and
controlling operation of the display based on determining whether the position of the eye is within the combined registration volume, wherein controlling the operation of the display includes providing, to the user, a notification of misregistration based at least partly on determining that the eye is not within the combined registration volume.
10 . A computer-implemented method for controlling a wearable display configured to project light to an eye of a user to display virtual image content, the method comprising:
determining a display registration volume relative to the display such that the virtual image content is received by the eye while the eye is situated within the display registration volume;
determining a housing registration volume relative to the frame such that an external field of view of an external environment proximal to the display is viewable by the eye while the eye is situated within the housing registration volume;
determining a combined registration volume that includes a plurality of points that are included in both the display registration volume and the housing registration volume;
determining a three-dimensional (3D) position of the eye based on one or more images of the eye obtained with one or more eye-tracking cameras configured to image the eye while the display is being worn by the user;
determining whether the position of the eye is within the combined registration volume; and
controlling operation of the display based on determining whether the position of the eye is within the combined registration volume, wherein controlling the operation of the display includes providing, to the user, a notification of misregistration based at least partly on determining that the eye is not within the combined registration volume.
11 . The computer-implemented method of claim 10 , wherein the combined registration volume includes all of the points that are included in both the display registration volume and the housing registration volume.
12 . The computer-implemented method of claim 10 , wherein the housing registration volume is defined relative to one or more housing openings in the frame.
13 . The computer-implemented method of claim 12 , wherein the housing registration volume has a cone-like shape with a base defined by the shape and size of the one or more housing openings.
14 . The computer-implemented method of claim 10 , wherein the position of the eye is a center of rotation of the eye.
15 . The computer-implemented method of claim 10 , wherein the display registration volume has a frustum shape.
16 . The computer-implemented method of claim 10 , wherein the notification of misregistration is provided to the user based on determining that the position of the eye is more than a threshold distance outside of the combined registration volume.
17 . The computer-implemented method of claim 10 , wherein the display registration volume is defined based at least partly on a type of application associated with virtual content being presented through the display.