More news on the next iOS smartphone coming from Apple today, with word that Sony has now been pulled in by Apple to manufacture the in-cell panels for the new iPhone, or iPhone 5 as it is being referred to, and will apparently being making the panels alongside the other companies.

According to the guys over at Apple Insider, an article on the Taipei Times has it that Sony began making the in-cell panels in February and is to ramp up production this month in prep for the expected fall launch of the iPhone 5.

In-cell panel technology enables thinner smartphones, as the design embeds the touch sensors into the LCD filter array rather than stacking 2 components on separate glass pieces, but apparently due to the complexity the average fabrication yield rate is somewhat low and thus Apple has needed to get the components from several suppliers.

Sony joins South Korea’s LG Display, Toshiba Mobile and Sharp Corp to deliver the in-cell panels in enough quantity for the expected launch of the next iPhone.

According to Stone Wu, an analyst for IHS Displaybank, even if all the companies began mass production of in-cell panels in May, they can only hit an average yield of 65% to 70% at present, whilst firms that make the IPS units like in the current iPhone 4S hit yield rates of roughly 80% to 85%.

AU Optronics, an Apple supplier that is rumoured to be supplying LCD’s for the Apple iPad Mini, is readying in-cell products, as is Chimei Innolux, but both firms are not expected to partner Apple as their plants will not be ready until Q2 2012.