Rumours have surfaced recently claiming Apple is considering a potential change in the touch technologies used for next generation iPhones and iPads. Although Digitimes heard that Apple would use the in-cell technology for iPhone 5S (or 6), the news of Innolux delivering TOD (touch on display) samples broke in the first days of January. Next came the news that Innolux and AUO have provided one-glass-solution (OGS) samples for the iPad mini.
Now what’s the likelihood of Apple utilising these technologies? To spot their potential and drawbacks, we need to understand how these technologies work first and Calvin Hsieh of NPD DisplaySearch helps us in doing that.
TOD is an Innolux-developed technology and is a “type of on-cell touch structure in which the sensor is located on the upper glass (the color filter substrate), beneath the top polarizer”. This technology combines LCD and touch, so Innolux needs to meet Apple’s LCD display requirements to be accepted.
OGS integrates the touch ITO (Indium tin oxide) sensor circuits into the cover glass. The situation gets complicated because there are two OGS methods: a piece type – like TPK’s TOL (touch on lens) solution – and a sheet type. Each uses a different process, but the X-Y sensor patterns are on the same side, therefore the sensor structure is called “SITO” or “G2″.
So far LG Display delivers total integration in iPhone 5 panel suppliers, from LCD to cover glass lamination, while Japan Display and Sharp only manufacture the in-cell LCDs. Now, assuming the OGS technology will pass the tests and Apple will proceed by using it, the question is whether it will choose Innolux and AUO or TPK?
A possible scenario as seen my Hsieh:
- OGS sheet type: AUO and Innolux offer LCD, OGS patterning (cover glass with SITO sensor) and lamination in an integrated solution. The glass sheet could be specified by Apple as IOX-FS next version, which will likely reach Gorilla 1’s compressive strength standard. In this scenario, LG Display will never give up and must be one of the suppliers.
- OGS piece type: AUO and Innolux offer LCD, piece type sensor patterning, and lamination. Unlike sheet-type integration, they can use consigned cover glass pieces from existing finishers such as Lens One. The challenge will be to expand their piece-type patterning equipment, yield rate and throughput. After all, iPhone is more than 100M unit base.
Although Innolux and AUO have the strength to offer integrated solution, they have just started offering OGS solution. On the other hand, TPK has been part of Apple’s supply chain for a while now, and has been working on this solution for several years. TPK also has the strength in OGS integration from sensor patterning and cover glass finishing to module lamination. In other words, it is highly likely to remain as Apple’s supplier.