Interesting discussion about how glasses might be used in this territory, and I find myself wondering about contact lenses.
Haven't we solved most of the basic problems here?
* We know that flexible displays can be constructed.
* We know that it's possible to make a display material that's also transparent
* We know that we haven't reached peak pixel density yet: what DPI level would suffice for a lens-sized display?
* Contact lenses already comprise a focusing medium
* Well made and maintained ones can cover most of the cornea if necessary (especially if routinely worn for no longer than, say, 10 hrs a day)
* There's abundant technology now for short-range high-bandwidth data transit
—so the only radically new feature of this item would be its power source: maybe body heat conversion, or perhaps (if the energy requirements are low enough) some kind of localised wireless power transmission. However sci-fi that may seem, I am one of those whose boyhood rites of passage included building my own crystal radio (back in the 1960s) so I know that it's possible to extract useful energy from an AM radio signal coming from 200 miles away. How much energy does a display need if it's < 3cm away from your retina?
All the heavy CPU work would be done by the connected device in your pocket, so the lens has to do only one thing: authenticate (pair with) and display an image feed.
Maybe in 15 years my daughter will routinely ask the optician for prescription 'active' lenses, instead of old-fashioned 'passive' ones, so that she can use a cornucopia of AR content and help beamed from her phone.
(Hacking could be a problem, mind you ... and, hm, temperature regulation?