Our eyes are just not built for the future. It sucks, but it's true. We can't physically focus on things that are very close to us, which is why we're not all rocking high-resolution immersive virtual reality displays built into our eyeglasses. How do we fix this problem? Simple: we upgrade our eyeballs.
We've posted about head-mounted VR displays a lot around here, but there's always a compromise going on: you can have a small, slick system that projects a little image with a narrow field of view, or you can have a gigantic bulky system that projects a big image with a wide field of view. The reason that you can't have the best of both worlds (a big projected display in a small system) is that our eyes simply cannot focus on images displayed at the distance of a pair of glasses. We can sort of fake it by fooling our eyes into thinking that the image is actually farther away, but doing this takes a lot of clunky optics, especially if you're going for something that looks halfway decent.
The obvious solution, then, is to modify our eyes to enable them to focus on objects that are much, much closer. It's not very hard to do this: you just need contact lenses. The hard part is creating a contact lens that keeps the rest of the world in focus while allowing you to view extremely close-up displays at the same time, but this is what a company called Innovega has managed to do.
Innovega's iOptik contact lenses have special filters and secondary lenses built into them that block out all of the light from close-up displays except for a narrow beam that's refocused by the lens itself and fired straight back into your pupil. These filters only block the light emitted by the display itself (very narrow bands of red, green, and blue light), leaving the rest of your vision unaffected such that when the display is off, it's just like you're wearing a normal contact lens. When the display is turned on, a "lenslet" at the center of the lens refocuses the display so that you can see it, and a secondary filter behind that lenslet blocks out the rest of the visible spectrum so that you don't get a blurry dot at the center of your vision. Here's a handy diagram of all the different bits working together:
The upshot of all this is that you can put in an iOptik lens (it can have a conventional prescription or not), and you won't notice anything at all. It'll be just like seeing normally. But if you put a display up to your eye, it's magically in focus, and if that display is transparent, you'll be able to focus on it and the rest of the world at the same time, which is what makes augmented reality work. And since the focusing optics are in the lens itself and not the display system, the display can be as thin as you want without sacrificing field of view or resolution: we're talking an IMAX-style sunglasses display with a field of view of 80 degrees or better, which translates into viewing a 200-inch display from 10 feet for a 40-inch display from just two feet. It may even be possible to achieve a field of view of 120 degrees, which would cover practically everything you can see, allowing for true immersive virtual reality.
Innovega has these lenses all ready to go, and it's currently working under DARPA funding to create a prototype for the military. It should have a consumer version ready to rock in just two or three years for about the same price as regular contact lenses, and at that point, it'll be up to electronics manufacturers to come up with awesome news ways to take advantage of the potential here. VR sunglasses for real, man. It's going to be awesome.