Rachel Metz writes: I’m sitting in Gordon Wetzstein’s lab at Stanford University with a hacked-together prototype of a head-mounted display strapped to my face, using a wireless Xbox controller to manipulate a series of 3-D models: a lion, a chessboard filled with chess pieces, an espresso machine, and so on.
“…the technology has improved immensely in the last couple years, there are still plenty of crucial issues to be sorted out—among them that feeling of motion sickness that some people like myself have when experiencing virtual reality, which arises from what’s known as vergence-accommodation conflict.”
The images are fairly simple, run-of-the-mill models—the kind that anyone could download from the Internet. What is interesting, though, is what happens as I stare at the models, turning them with the controller so I can inspect them from different angles: I can focus on the different parts of the images at different depths as I would when gazing at something in real life, so when I look at, say, the chess pieces up close, those in the background look fuzzy, and vice versa when I focus on the pieces in the distance. And I don’t feel nauseous or dizzy like I sometimes do when I’m playing around with virtual reality, especially when looking at objects that are close to my face.
“In real life, when you’re looking at something—a flower, for instance—your eyes move and the lens in each eye adjusts to bring whatever’s in front of you into focus. With stereoscopic 3-D, a technology commonly used by companies making virtual reality headsets, things gets trickier.”
Virtual reality is on the verge of commercial availability, with consumer-geared headsets like the Oculus Rift poised for release next year (see “Oculus Shows Its First Consumer Headset, Circular Hand Controls”). Yet while the technology has improved immensely in the last couple years, there are still plenty of crucial issues to be sorted out—among them that feeling of motion sickness that some people like myself have when experiencing virtual reality, which arises from what’s known as vergence-accommodation conflict.
This conflict is what Wetzstein, an assistant professor of electrical engineering, and other researchers at Stanford are trying to solve with the headset I tried on, which they call a light field stereoscope—essentially, a device that uses a stack of two LEDs to show each eye a “light field” that makes virtual images look more natural than they typically do.