Contact lenses can not only help against astigmatism, near- or farsightedness but could help to make virtual worlds more alive.

These contact lenses would create the blurriness of elements which are not in immediate focus hence increasing the perception of depth of a virtual reality scene.

If we focus on a close object, the backround becomes blurry (which we usally don't notice as we focus on the close object...)
This effect could be mimicked with a smart contact lens that turns blurry in various segments depending on what needs to be focused.