A mixed reality system for displaying virtual holograms using a head mounted display and a tracking device. The HMD has one or more cameras mounted on its exterior connected to a portable computing device. The cameras record what a user's eyes would see in the environment and project the images onto the screen panel display. The cameras also transmit tracking device data to a software application installed on a portable computing device. Light emitting diodes serve as tracking points for the detection algorithm. The tracking device can be configured to transmit data to the portable computing device via optical modulation. Less private radio frequency technologies can be employed such as Bluetooth or WiFi to enable one-way or two-way communication. In some embodiments, multiplexing can be implemented to enable identifying and differentiating multiple tracking devices in a single frame.