iPads and Retina Displays: Doing the math
Over the weekend, we saw the swirling rumors around the specs for the (presumably inevitable) iPad 2 start to come together. One of the most intriguing suggestions, which Engadget claims to have a reliable source for (and MacRumors some corroborating evidence to boot) is a higher resolution screen to match the iPhone 4′s Retina Display — specifically, doubling in both directions, changing from 1024×768 to 2048×1536.
This has prompted some discussion around exactly what Retina Display means, and whether this would count. The iPhone 4′s screen is a mammoth 326 pixels-per-inch (ppi), whereas this rumored new iPad resolution is a somewhat lesser 264 ppi — quite a bit less. However, I believe it’s just as valid for Apple to call this a Retina Display as it was to call the iPhone 4 screen, and after the break I will explain why with some hopefully convincing mathematics.
Firstly though, it’s important to stress that these are only rumors and that 2048×1536 is an incredible number of pixels — 3,145,728 of them, in fact. That’s only 17 percent less than the 27″ iMac or 27″ Cinema Display, and it’s 52 percent more pixels than a 50″ 1080p television screen! This makes the screen expensive to make; it places greater strain on the graphics chipset to drive the screen, which makes that more expensive, too; it won’t do the battery life any favors either. All of this, to my mind, suggests this is one rumor that might come down to wishful thinking. As John Gruber said: “I’ll believe it when I see it.”