Here are three shots at 10X magnification of my iPad 3, iPad Mini, and Kindle Fire HD. Ignore the blue background, as it’s an artifact of the processing software. All three shots were taken with the font set at the same size. I’m using a very old Intel Play USB microscope, which is quite obsolete now. (I have a new microscope on order and will re-do these when it comes in, but I thought they would be fun for you to see now.) Of course the iPad 3 is the winner, but the Kindle Fire HD gives the Mini a run for its money.
Click on each picture for a larger image.