US 11,998,275 B2
Eye tracking using aspheric cornea model
Richmond B. Chan, Arlington Heights, IL (US); Wenyi Zhao, Weston, FL (US); and Bing Wu, Davie, FL (US)
Assigned to Magic Leap, Inc., Plantation, FL (US)
Appl. No. 18/004,979
Filed by Magic Leap, Inc., Plantation, FL (US)
PCT Filed Jul. 14, 2021, PCT No. PCT/US2021/041618
§ 371(c)(1), (2) Date Jan. 10, 2023,
PCT Pub. No. WO2022/015847, PCT Pub. Date Jan. 20, 2022.
Claims priority of provisional application 63/140,202, filed on Jan. 21, 2021.
Claims priority of provisional application 63/139,750, filed on Jan. 20, 2021.
Claims priority of provisional application 63/052,392, filed on Jul. 15, 2020.
Prior Publication US 2023/0210365 A1, Jul. 6, 2023
Int. Cl. A61B 3/113 (2006.01); G06F 3/01 (2006.01)
CPC A61B 3/113 (2013.01) [G06F 3/013 (2013.01)] 18 Claims
OG exemplary drawing
 
1. 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 and a pupil, said display system comprising:
a frame configured to be supported on a head of the user;
a head-mounted display disposed on the frame, said display configured to project light into said user's eye to display virtual image content to the user's vision field;
one or more eye tracking cameras configured to image the user's eye;
a plurality of light emitters; and
processing electronics in communication with the display and the one or more eye tracking cameras, the processing electronics configured to:
receive images of the user's eye captured by the one or more eye tracking cameras, wherein glint reflections of the different light emitters are observable in said images of the eye captured by the one or more eye tracking cameras; and
estimate a location of a corneal center of the user's eye based at least in part on the locations of the glint reflections in said images captured by said one or more eye tracking cameras,
wherein said processing electronics employ an aspheric model of said cornea in numerical calculations to estimate said location of said corneal center of the user's eye,
wherein said processing electronics additionally employ a spherical model of said cornea in further numerical calculations to estimate said location of said corneal center, and
wherein said estimate of said corneal center determined from a spherical model of said cornea is applied to said aspheric model in the numerical calculations to determine a location of said corneal center.