A Taiwanese firm will be the biggest supplier of backlight units (BLUs) for the iPad 3, according to reports from the region.

Digitimes says that Radiant Opto-Electronics will be the dominant supplier of BLUs for the iPad 3 having been engaged by both LG and Samsung to supply BLUs for LCD panels that will in turn be supplied to Apple for the next-generation tablet.

LG will be the number one supplier of LCDs to Apple for the iPad 3, with Samsung in second place though it is likely to be closely followed by Sharp, the report states. Sharp also sources many of the BLUs it uses in LCD construction from Radiant, according to industry sources cited by Digitimes.

The report adds weight to evidence from other sources that Apple has chosen the component suppliers for the iPad 3. Trial production could begin in October for an early 2012 launch, it has been claimed.

There has been some speculation that backlight units capable of supporting a higher-resolution display, as the third-generation iPad is rumoured to have, are more bulky than BLUs used in the current iPad, making the construction of the iPad 3 problematic.

Apple's A6 chip to boost speed, battery life in next iPad

Meanwhile, Apple's major touch-panel supplier, TPK Holding, has revised its outlook for Q3 2011, a separate report on Digitimes claims. TPK still expects overall sales to fall in the third quarter, though thanks to orders from new clients - the report doesn't name these clients, unfortunately - the dip in sales won't be as bad as first feared.