The Googles told me 60PPD (1): "If there is any single number that people point to for resolution, it is the 1 arcminute value that Apple uses to indicate a “R

The Googles told me 60PPD (1): "If there is any single number that people point to for resolution, it is the 1 arcminute value that Apple uses to indicate a “Retina Display”. This number corresponds to around 300 PPI for a display that is at 10-12 inches from the eye. In other words, this is about 60 pixels per degree (PPD)." 1.) https://www.anandtech.com/show/7743/the-pixel-density-race-and-its-technical-merits https://www.anandtech.com/show/7743/the-pixel-density-race-a...