Thales Visionix, a division of Thales Defense & Security, Inc., specializes in advanced helmet-mounted display (HMD) and motion tracking technologies designed for high-performance aerospace, defense, and industrial applications. Headquartered in Aurora, Illinois, Thales Visionix develops HMD technology, while their Billerica, Massachusetts office focuses on motion tracking and sensor fusion technologies, marketed under the InterSense brand. In a strategic move, Thales acquired the Visionix HMD and InterSense motion tracking businesses from Gentex Corporation in December, 2012, establishing Thales Visionix, Inc. as a wholly-owned subsidiary. Under a U.S. Department of Defense proxy agreement, Thales Visionix continues to operate from its Aurora and Billerica locations with the original management team in place, driving forward its mission in HMD and motion tracking advancements.