US Patent 10152141 Controller movement tracking with light emitters

A head-worn computer includes a camera system positioned to capture a surrounding environment in front of a user, a processor that identifies a position of a plurality of light emitters mounted on a hand-held controller from images captured by the camera system and tracks the position of the plurality of light emitters as the hand-held controller moves in the surrounding environment and interprets the tracked position as positional changes of the hand-held controller. The processor uses the position of the plurality of light emitters as markers in three dimensional space, the markers used as an anchor for virtual content presented in a see-through display of the head-worn computer.