Apple may risk iPad 3 display shortage

Apple could struggle to keep pace with demand for the iPad 3, thanks to  a fragile supply of its new Retina display.

The tablet’s 2,048 x 1,536 display offers 3.1 million pixels — four times the number in the iPad 2 and a million more than an HDTV, says Apple. It’s a pixel density of 264 ppi.

And while it doesn’t match up to the Retina display of the iPhone 4, which boasts a pixel density of 326 ppi, it’s a major selling point of the device.

But according to display analyst NPD DisplaySearch, it’s been quite a challenge to manufacture. The displays are believed to be produced by Sharp, Samsung, and LG Display – and Sharp may be having some difficulty.

“Our understanding is that Sharp has been producing samples of the iPad 3 display using IGZO TFTs, but it is not clear whether the quality or manufacturing yields are acceptable to Apple and Sharp,” says NPD.

“There has been speculation that Sharp has switched back to a-Si TFT production while they work on the IGZO process; meanwhile, our research indicates that Samsung and LG Display are producing the new panels using a-Si TFT.”

And this won’t have been easy, as 264 ppi is generally believed to be the upper limit of pixel density for a-Si TFT.

Given all this, it may prove difficult for Apple to maintain supply if demand for the iPad 3 turns out to be as high as expected.

“The company finally achieved supply/demand parity for iPad 2 shipments in the second half of last year,” says NPD.

“How quickly panel suppliers are able to ramp up production will be the ultimate determining factor in terms of meeting the typical surge in demand associated with new Apple products.”

Regardless of the TFT technology used, the doubling of the pixel density means a significantly smaller aperture ratio, which means that a brighter backlight is needed.

The iPad 3 panel appears to have at least twice as many LEDs as the iPad 2, which had 36. Even allowing for increases in LED efficiency, this is likely to push up power consumption considerably, requiring a bigger battery – one reason for the iPad 3’s slightly larger and heavier case.