My iPad screen turned white but apps seem to still be running.

My iPad Air screen suddenly went white with some black vignette around the edges. When I turned it on it had a few stripes of grey and some grey dots approximately where the app icons would have been but they eventually faded to white. I have tried hard rebooting it (holding the top button and the home button together for 10 seconds). I also reset and restored it through iTunes and updated the iOS, but it didn't change anything. I had been able to get it back to normal for a couple minutes by just randomly pressing buttons, however it was short lived. Another time I was able to get it back (sort of) but there was a white vignette around the edges. Any thoughts on what might be happening? It has not been dropped or exposed to heat, cold or moisture.