US 12,265,221 B2
Electromagnetic tracking with augmented reality systems
Brian Bucknor, Miramar, FL (US); Christopher Lopez, Davie, FL (US); Michael Janusz Woods, Mountain View, CA (US); Aly H. M. Aly, Coral Springs, FL (US); James William Palmer, Miami, FL (US); and Evan Francis Rynk, Boca Raton, FL (US)
Assigned to MAGIC LEAP, INC., Plantation, FL (US)
Filed by Magic Leap, Inc., Plantation, FL (US)
Filed on Aug. 24, 2022, as Appl. No. 17/894,845.
Application 17/894,845 is a continuation of application No. 17/171,328, filed on Feb. 9, 2021, granted, now 11,460,698.
Application 17/171,328 is a continuation of application No. 16/670,172, filed on Oct. 31, 2019, granted, now 10,948,721, issued on Mar. 16, 2021.
Application 16/670,172 is a continuation of application No. 16/288,856, filed on Feb. 28, 2019, granted, now 10,495,718, issued on Dec. 3, 2019.
Application 16/288,856 is a continuation of application No. 15/495,597, filed on Apr. 24, 2017, granted, now 10,261,162, issued on Apr. 16, 2019.
Claims priority of provisional application 62/479,111, filed on Mar. 30, 2017.
Claims priority of provisional application 62/328,003, filed on Apr. 26, 2016.
Prior Publication US 2022/0404622 A1, Dec. 22, 2022
This patent is subject to a terminal disclaimer.
Int. Cl. G02B 27/01 (2006.01); G01S 1/68 (2006.01); G01S 1/70 (2006.01); G01S 5/02 (2010.01); G02B 27/00 (2006.01); G06F 1/16 (2006.01); G06F 3/01 (2006.01); G06F 3/16 (2006.01); H01H 9/02 (2006.01)
CPC G02B 27/017 (2013.01) [G01S 1/68 (2013.01); G01S 1/70 (2013.01); G01S 1/7038 (2019.08); G01S 5/0247 (2013.01); G01S 5/0284 (2013.01); G02B 27/0093 (2013.01); G06F 1/163 (2013.01); G06F 3/012 (2013.01); G06F 3/014 (2013.01); H01H 9/0228 (2013.01); H01H 9/0235 (2013.01); G02B 2027/0138 (2013.01); G02B 2027/0178 (2013.01); G02B 27/0179 (2013.01); G02B 2027/0187 (2013.01); G06F 3/165 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A head-mounted display system comprising:
a display positionable in front of eyes of a wearer;
an electromagnetic (EM) field emitter configured to generate a time-varying magnetic field, wherein the EM field emitter includes a multiplexing circuit configured to multiplex the magnetic field;
an EM sensor configured to sense the magnetic field;
a processor programmed to:
receive signals from the EM sensor indicative of the sensed magnetic field; and
analyze the received signals to determine a position or an orientation of the EM sensor; and
an on-board real-time clock (RTC) associated with the EM field sensor, wherein the EM field sensor is configured to synchronize the RTC with a corresponding RTC of the EM field emitter.