the light source has to be bright at an angle
to see what is all under your screen you have to have a brightly lit room and you have to have good near sighted vision, tilt the ipad air or retina mini in all directions but still laying flat, I mean, lift each corner slightly and scan the screen, you'll find nice tiny shimmering dust of make up or aluminum dust or industrial debris tiny enough to end up in the assembly line and into your screen. the poorest quality control ever. i've already returned over 14 airs and minis.
to see what is all under your screen you have to have a brightly lit room and you have to have good near sighted vision, tilt the ipad air or retina mini in all directions but still laying flat, I mean, lift each corner slightly and scan the screen, you'll find nice tiny shimmering dust of make up or aluminum dust or industrial debris tiny enough to end up in the assembly line and into your screen. the poorest quality control ever. i've already returned over 14 airs and minis.