Man you are starting BS here, although no short of such things in this thread, I urges us do some more constructive talkings.
relax, I'm just floating some ideas.
You mean a Luneburg lens?
Doesn't look like it. This is what the Luneburg lens used on the F22 looks like.
As for the rest, well has there ever been a case in recorded history where a prototype has defected? Not just anyone can become a test pilot you know, and when was the last time a Chinese pilot defected?
There is honestly more chance an American pilot would fly his F22 to China in exchange for fat stacks since these are operational pilots, and there are far more of them. But that's not going to happen, so talk of J20 going walkies is equally absurd.
Apparently the last deflection happened in 1990, and this was only a list of deflections during cold war years. I did noticed that all of them involved operational and usually old planes. Curiously there is quite hight incidence of deflections using J-6s. [video]http://en.wikipedia.org/wiki/List_of_Cold_War_pilot_defections#China[/video]
I agree the thing doesn't look like Luneburg lens. (actually I have a feel that it's not the luneburg lens before making the suggestion but I'm just floating some possibilities.)