The piSight 166-43 has a horizontal field of view of 164 degrees, which approaches the human visual field.
Building, testing and shipping such a high-end HMD is always a cause for celebration here. We sell lots of 120-degree and 60-degree products every year, but just a handful of the super high-end ones.
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It takes one or two computers to drive the HMD to its full potential, and we typically recommend driving it with four HD1080P or 1920x1200 signals which feed into our video processing electronics.
The field of view is just spectacular, as well as the level of detail across it. It is simply fun to see how immersive such product is.