He remains unsure at this point whether Apple will introduce a major new display technology for iPad 5. "It is not yet clear if there will be a big change to the display -- such as using IGZO," he tells CNET.
IGZO, for indium gallium zinc oxide, refers to the oxide-based thin-film transistors, unveiled by Sharp almost exactly two years ago. Many predicted that Apple would introduce it with the iPad with Retina display in the spring of 2011.
As the Rollup reported in late 2011, IGZO transistors deliver better performance than that of amorphous-silicon transistors, currently in wide use, according to the summary at Semiconductor Portal. As a result, IGZO transistors can be made smaller without sacrificing performance, a move that lets more light pass through the panel. "This advantage translates into lower power consumption and higher resolution. Sharp reported a reduction in power consumption of about 33% for a 10-inch-wide prototype panel compared to an equivalent panel with amorphous-silicon TFTs," according to Semiconductor Portal.
But by making the kinds of changes Semenza outlines, Apple may be able to improve display characteristics and make the display thinner and presumably lighter, without having to gamble now on a still-new technology that may not have achieved the kinds of manufacturing yields needed for high-volume and affordable 9.7-inch screens.
There's been speculation, in fact by Semenza's colleague Calvin Hsieh in January 2012, that Apple is moving to new display technologies. The real question is when. There's been speculation that the next full-size iPad will make use of the same glass/film dual indium tin oxide touch panel structure introduced in the iPad mini (this is usually abbreviated as GF2 or G/F2 DITO), as the Rollup has previously noted. [see "iPad 5 will have GF2 DITO OMG IMHO screen structure"]
ITO is used to make transparent conductive coatings for touch screens and other displays. DITO means the coating can be layered on both sides of single substrate, again reducing the number of layers in the display.
This speculation was repeated this week by KGI Securities analyst Ming-Chi Kuo, whose most recent Note to Investors was cited in a blog post at iClarified. Kuo says iPad 5 will be 15% thinner and 25% lighter than the current iPad, in part due to using the GF2 DITO technology.
He argues that a more power-efficient display and an updated processor, dubbed the A7x, will also result in a thinner battery. And not just thinner: "We therefore think that iPad 5's battery capacity will be 25-30% smaller, at 8,500-9,000mAh, than iPad 4's, and the battery's thickness will be 15-20% smaller, at 7.5-8.0mm, and the number of cells will be reduced to two from three."
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