John Carmack's prototype head mounted display
Essentially, the Oculus Rift contains a 1280 x 800 screen split in two — 640 x 800 for each eye — with an image that really needs to be seen to be believed. While the images themselves are relatively low-resolution, the immersion factor is pretty fantastic. That's due to the Rift's 90 degree field-of-view, something you won't find in most other HMD's (including Sony's recently-launched 3D head mounted display, which Carmack praised for its high quality and relatively low price point). As you can see in the video, the sides of the round eyepieces have been literally taped off to hide some of the end-of-screen effect that might take away from the experience (reminder: early prototype). The Rift also helps by being surprisingly thin and light, even in this prototype form. The framerate was also a smooth 60fps — something that Carmack focused on almost as much as the latency issue itself.