Why a "retina" display might not come to iPad until next year

Numerous rumors have proclaimed that the second-generation iPad—expected to ship in early April—will have a higher resolution display. However, some sources now seem certain that the resolution will remain the same, and that iPad users may have to wait until the “iPad 3” for sharper text and graphics.

The 326ppi “retina” display of the iPhone 4 quickly made the iPad’s 1024 x 768 pixels look decidedly fuzzy when spread over 9.7 diagonal inches. Many assumed Apple would bring a retina-class display to the next iPad, though matching the same pixel density as the iPhone 4 could likely be technically unfeasible, surpassing the pixel count of Apple’s LED Cinema Display.

Doubling the linear resolution to 2048 x 1536 pixels, though, would result in a pixel density of 260ppi, a figure close enough to appear nearly as sharp as an iPhone 4 to the average viewer. Pixel-doubling would make development of updated apps simple, since the same basic technique was successfully used for the iPhone 4. Additionally, apps that hadn’t been updated could be scaled automatically to fit the higher resolution. (Scaling to other resolutions would result in added blurriness from anti-aliasing, as noted by TiPB.)

One recent rumor from Engadget cited a source that claimed the new iPad “will sport a new screen technology that is akin to (though not the same as) the iPhone 4’s retina display and will be “super high resolution.” Graphics files found within recent versions of iBooks point to a “2x” screen size, and Taiwan-based DigiTimes cited sources within component makers in Asia that specifically mentioned a 2048 x 1536 pixel display.

While moving to such a display is technically feasible, others are not so sure Apple is ready to produce an iPad with a higher resolution. Serial tech entrepreneur Kevin Rose—who has a questionable track record making prognostications on upcoming Apple products—claimed last week that there would be no resolution change for the next iPad according to an “iPad source.” Daring Fireball, having a much better record on nailing future hardware specs, cited its own sources that said the second-gen iPad will not have a “retina display” and will remain at 1024 x 768.

Daring Fireball suggested that such a high-resolution display would be cost prohibitive due to the GPU and RAM improvements needed to support it. However, the iPad is also rumored to include a next-generation processor including two ARM Cortex A9 cores and two improved Imagination Technologies PowerVR GPU cores, which could easily provide the processing power for a 2048 x 1536 screen.

Instead of technology or cost considerations, market research firm IDC has suggested this week that the move to higher resolution is likely being delayed by manufacturing volume constraints.

“Our sources say Apple has requested that manufacturers begin work on displays with [2048 x 1536] resolution for the iPad 3,” IDC research manager Tom Mainelli told DigitalArts on Monday. “I don’t believe anybody is ready to produce that resolution in volumes at this point. And Apple is going to require huge volumes for the iPad 2.”

IDC said in a report last week that it expects the “media tablet” market to grow from sales of about 17 million units in 2010 to over 44 million this year. Apple grabbed at least 85 percent of media tablet sales in 2010, and IDC believes Apple will still hold a “lion’s share” of that market in 2011. In order to procure enough displays to churn out iPads in the neighborhood of 30-40 million units, Apple may have had to hold off on a resolution bump this time around.