Why the new iPad is so hot (literally)

Updated. That super crisp and bright Retina display of the new iPad(s AAPL) might be easy on the eyes, but some reports indicate it may not be very easy on your hands or lap, thanks to the heat it throws off.
A Dutch tech site, Tweakers.net, did a thermal image comparison of the new iPad and its predecessor, the iPad 2. Here’s what they found (translated from Dutch via Google):

A new iPad was placed next to an iPad 2, both tablets were entrusted with the GLBenchmark. After five minutes, per tablet, the temperature of the hottest point is measured. On the left is the new iPad. Noted that the lower right corner at the rear a temperature of 33.6 ° C. The iPad 2 scored in the same place a temperature of 28.3 ° C, a difference of 5.3 ° C.

Image credit: Tweakers.net

Of course, a difference of 5.3 degrees Celsius is actually a difference of about 10 degrees Fahrenheit (33.6  ° C = 92.48 ° F and 28.3 ° C = 82.94 ° F), which explains why people are noticing the temperature difference.
But where is the heat coming from? Some possibilities:

  • The graphics processor. While Apple held over essentially the same processor for the new iPad from the iPad 2, it did bump up the graphics with a quad-core processor. It’s possible this is contributing to the heat.
  • The LTE chip. Sure, this is the first iPad with a 4G radio inside, but it’s only an option. Those who’ve ordered WiFi-only versions of the new iPad, including our own Kevin Tofel, also report that this device is noticeably warmer.
  • The display. This is probably most likely — as we’ve written about before, the new Retina display packs four times the number pixels as its predecessor. In addition, the new iPad also likely sports “at least twice as many” LEDs for lighting the display, according to the experts at DisplaySearch. The iPad 2 has 36 LEDs, so it’s possible that the heat-emitting culprit is the possibly 72 LEDs that light up that Retina screen.

Still, despite the warmer temperature of the new iPad, Apple’s done something right with the battery. Despite a brighter display — and more graphics processing power — the new iPad is promising nearly the same battery life as the iPad 2: 10 hours for WiFi-only and nine hours on a cellular connection.
Update: Apple says the new iPad operates “well within our thermal specifications,” according to a statement given to the blog, The Loop. Without saying what those are, Apple’s spokeswoman Trudy Muller suggested any customers concerned about the heat issue “should contact AppleCare.”
Update 2: Consumer Reports  has weighed in and its product testers don’t think the new iPad’s temperature increase compared to previous iPads is much to worry about. The magazine did a series of tests, including running a graphics-intensive game on the new iPad for 45 minutes, and added some variables. Here’s what they found:

So, when plugged in, the back of the new iPad became as much as 12 degrees hotter than the iPad 2 did in the same tests; while unplugged the difference was 13 degrees.
During our tests, I held the new iPad in my hands. When it was at its hottest, it felt very warm but not especially uncomfortable if held for a brief period.

Thumbnail image courtesy of Flickr user hoyasmeg