When peering through a virtual reality headset, players can't see their hands--or use them to interact with their digital surroundings. To solve VR's interaction problem, software developers Robert Wang, Chris Twigg, Kenrick Kin, and Shangchen Han formed a start-up, courted investors, and got to work.

The four had spent years working with motion-tracking camera systems and developing algorithms that monitor and analyze skeletal structure. With their experience, it didn't take long to craft software that tracks joint angles and knuckle placement to create realistic virtual hands. But they couldn't find a camera sensitive enough to pick up such data. "We played with them all," Wang says. "There was no depth-sensing camera good enough for VR hand tracking." Existing videogame motion trackers, such as Microsoft's Kinect, are designed to detect large objects, such as a bouncing 8-year-old several feet away, not subtle hand movements.