Google Launched Project Cardboard an incredible open design (apparently in Public Domain, or I may have failed to spot the license):
Virtual reality has made exciting progress over the past several years. However, developing for VR still requires expensive, specialized hardware. Thinking about how to make VR accessible to more people, a group of VR enthusiasts at Google experimented with using a smartphone to drive VR experiences.
The result is Cardboard, a no-frills enclosure that transforms a phone into a basic VR headset, and the accompanying open software toolkit that makes writing VR software as simple as building a web or mobile app.
By making it easy and inexpensive to experiment with VR, we hope to encourage developers to build the next generation of immersive digital experiences and make them available to everyone.ù
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