VR headache

One of the biggest problems virtual reality headsets have yet to overcome is the headaches they cause in a subset of users. For a lot of users, this is caused by needing to rapidly switch your focus between objects that are (virtually) near and far away. "Trying to focus on 'far away' objects on that stereoscopic screen means keeping a fixed focal distance but changing the 'vergence' angle of your eyes—in essence, going a little cross-eyed for a moment." Fortunately, researchers at Stanford have figured out a partial solution.

They "created a prototype headset (PDF) that includes a translucent LCD panel sitting about 1cm in front of a standard, opaque LCD. With some GPU pre-processing, this 'light field stereoscope' headset can display nearby objects on the front LCD and farther-away objects on the rear, creating what the researchers call a '4D' image that layers a basic virtual light field on top of the usual stereoscopic left/right eye 3D separation." This provides an easy, low-tech way to let the eyes focus more easily, and alleviate the strain that causes headaches.