One of the most fun design considerations for VR is how to work with peripheral vision. Most two dimensional designs focus on the central 70 degrees of your vision. That central part is where almost all of your cones are that let you see color and give you your visual acuity. Your full field of view though is about 180 degrees and that remaining 110 degrees is your peripheral vision. While the Oculus and Vive aren’t perfect, limiting viewers to a field of view of only 110 degrees, designers still get 40 degrees of peripheral vision to work with.
Your peripheral vision is primarily made up of rods that help you see in the dark and detect motion. You can do a cool experiment to check how the motion detectors work. Wiggle a finger in front of your face while staring straight ahead. Then start moving it out towards the side of your vision while still looking ahead. Keep your finger moving as it hits the edge of your vision. Then stop wiggling your finger. It should vanish—out at the edge of your vision what you see is primarily motion. That ability to detect motion has pretty strong evolutionary roots—your odds of surviving are better if you can detect that leaping mountain lion out of the corner of your eye than if you miss it. But your brain isn’t just hardwired to detect the mountain lion—it is also hardwired to respond (Move! Run!).
What that means for designers is that when people detect motion out of the corner of their eyes, they feel something. That emotional response is something that we, as artists, can work with. We can increase the sensory impact of our performances through activating the viewer’s peripheral vision. We talked earlier about attempting to build a language of visual music and our use of the viewer’s peripheral motion detector is part of the grammar of that language.
What you will see in our worlds is that nothing ever sits still, which keeps you visually stimulated across your full field of view. We spend a lot of design time thinking about how those movements feel for the viewer and how to use movement to make the experience more powerful.
Ideally, we want a VR headset that lets us work with the full field of view. Those missing 70 or so degrees in an Oculus take away from the impact of the visual worlds that we create. The problem is that a conventional lens can’t get close enough to the eye to have a full field of view without losing focus and having color shifts. A partial fresnel lens as used in the Oculus CV1 might be able to do better, but it remains a difficult challenge.