Apple has reportedly added two additional touch panel makers, Chimei Innolux and Cando, to its touch panel supplier list for iPad 2 in addition to current suppliers Wintek, Sintek Photronics and TPK Touch Solutions due to expanding market for the tablet PCs, according to industry sources.

Apple's orders of iPad 2 are expected to top six million units a month compared to a volume of four million units a quarter for the current version, pushing Apple to expand the number of touch panel suppliers, the sources noted.

Despite market reports stating that Apple is also likely to launch a 7-inch iPad as well as new iPhones, sources in Apple's supply chain in Taiwan claimed that they have not heard anything about orders for 7-inch touch panels.

But the sources confirmed that to their knowledge Chimei and Cando have landed touch-panel orders from Apple with shipments to begin in January or February.