Exactely, but it can be resolve with flexible fresnels with the focus center in front. The lenses could be curved until the edges are placed 180 deg from each eye. This way, the spherical distortions on the left and right eye are the same. If not, there coud be a severe stereographic error. There are some products on the market that uses also tilted optics similar to this HMD but the optics are rather aspherical onces.NVIS nVisor SX111 http://www.nvisinc.com/product.php?id=48 and SEOS http://cgsd.com/SEOSHMD/PalmerTech wrote:The problem is not so much the lack of proper focus as it is the disparity between the focus of each eye. Suppose that when looking directly forward, the center of each image is focused at 10 meters. Because each lens/display is tilted in opposite directions, the focus is going to change as you move your view across the field. Hypothetically, for example, you may be looking 10 degrees to the right of center, with the right eye having to focus at 5 meters and the left eye having to focus at 15 meters.
In addition, when you move your eyes, their physical position relative to the lenses is changing, changing the distortion slightly as well. Your brain can accept that pretty well when both eyes see the same geometrical changes, especially since those changes are the same no matter which way you look. I have done tests of setups like this, and a big problem is that any eye movement will result in mismatched distortion and focus between eyes that can cause significant eyestrain.
If eyetracking technology were more advanced, you could solve as least some of these problems with realtime distortion adjustment.
Damn, I forgot to mention the screens.
(french for moldy) and I don't think people want to wear something moldy on their face (even if it has 180° HFOV)
