Eye center of rotation determination, depth plane selection, and render camera positioning in display systems

A method implemented by a display system configured to project light to an eye of a user to display virtual image content in a vision field of said user, said eye having a cornea, an iris, a pupil, a lens, a retina, and an optical axis extending through said lens, pupil, and cornea, said method comprising:

• displaying, via the display system, virtual image content to the user's vision field;
• with an inward-facing imaging system configured to image said eye of the user to track movements of said eye, obtaining an estimate of a center of rotation of said eye based on a plurality of said eye images obtained with said inward-facing imaging system;
• and
• determining an estimate of a three-dimensional (3D) position of a center of rotation (CoR) of said eye based at least partly on a plurality of said eye images obtained with said inward-facing imaging system, wherein obtaining the estimate of the 3D position of the CoR includes:
• determining a plurality of potential 3D positions of the CoR, wherein each potential 3D position of the CoR is determined as a particular distance from a center of an estimated corneal sphere that includes the cornea of the eye;
• calculating a variation for each of the potential 3D positions of the CoR, wherein the variation is calculated based on an analysis of multiple images of the user's eye captured over a period of time;
• and
• determining the estimate of the 3D position of the CoR as the potential 3D position that exhibits the lowest variation among the plurality of potential 3D positions.

Non-transitory computer storage media storing instructions for execution by a display system of one or more processors, wherein the display system is configured to project light to an eye of a user to display virtual image content in a vision field of said user, said eye having a cornea, an iris, a pupil, a lens, a retina, and an optical axis extending through said lens, pupil, and cornea, and wherein the instructions cause the display system to:

• display virtual image content to the user's vision field;
• receive a plurality of eye images of said eye of the user, the plurality of eye images captured by an inward-facing imaging system configured to image said eye of the user to track movements of said eye;
• and
• obtain an estimate of a three-dimensional (3D) position of a center of rotation (CoR) of said eye based on the plurality of said eye images obtained with said inward-facing imaging system, wherein obtaining the estimate of the 3D position of the CoR includes:
• determining a plurality of potential 3D positions of the CoR, wherein each potential 3D position of the CoR is determined as a particular distance from a center of an estimated corneal sphere that includes the cornea of the eye;
• calculating a variation for each of the potential 3D positions of the CoR, wherein the variation is calculated based on an analysis of multiple images of the user's eye captured over a period of time;
• and
• determining the estimate of the 3D position of the CoR as the potential 3D position that exhibits the lowest variation among the plurality of potential 3D positions.