An augmented reality display system is configured to use fiducial markers to align 3D content with real objects. The augmented reality display system can optionally include a depth sensor configured to detect a location of a real object. The augmented reality display system can also include a light source configured to illuminate at least a portion of the object with invisible light, and a light sensor configured to form an image using reflected portion of the invisible light. Processing circuitry of the display system can identify a location marker based on the difference between the emitted light and the reflected light and determine an orientation of the real object based on the location of the real object and a location of the location marker.