Electromagnetic tracking with augmented reality systems

An augmented reality (AR) display system comprising a display configured to project virtual images to eyes of a wearer, a frame configured to mount the display in front of the eyes of the wearer, one or more cameras mechanically coupled to the frame and configured to capture images of an environment in front of the wearer, an electromagnetic (EM) field emitter configured to generate a magnetic field, an EM sensor configured to sense the magnetic field, wherein one of the EM field emitter or the EM sensor is mechanically coupled to the frame and the other of the EM field emitter or the EM sensor is mechanically coupled to a component of the AR display system that is independently movable relative to the frame and a hardware processor programmed to receive images of the environment in front of the wearer from the one or more cameras, receive signals from the EM sensor indicative of a sensed magnetic field, analyze the received images to determine whether the component of the AR display system is outside of a field of view (FOV) of the one or more cameras and determine a position of the component of the AR display system based on the received signals and whether the component of the AR display system is determined to be outside of the FOV of the one or more cameras.