Here at CEATEC 2012, Sharp is giving attendees a look at its new 5-inch 1080p LCD smartphone display, and at 443 ppi, it is one of the most pixel-dense panels we’ve ever seen. As we reported earlier, the company has recently begun mass-producing the displays, which we’ve learned use TFTs produced with continuous grain (CG) silicon rather than the company’s heralded IGZO transistor technology. While the resolution of the new 5-inch display falls a little short of the 498 ppi benchmark set by the 6.1-inch IGZO prototype we saw in June, they both looked equally impressive to our eyes (images of the new display below).
With all the interest in IGZO, we wondered why the company would decide to mass produce displays using CG silicon; an older technology. A Sharp rep explained that the polysilicon permits much higher pixel densities than IGZO in theory. The reason has to do with CG silicon’s higher electron mobility, which leads to a faster response time than that for IGZO transistors, allowing Sharp to pack many more of the tiny components into the same physical area. Also, since CG silicon is an older technology, Sharp was able to ramp up mass production sooner. It's interesting that while this is the largest display that Sharp has produced with a CG silicon TFT, it's already produced IGZO-based ones measuring upward of 30 inches.
In any case, Sharp’s new 5-incher is very impressive — along with LG’s, it's at the very top of the heap for next-generation smartphone display tech. And with companies like HTC reportedly already working on 5-inch 1080p phones, it could be no time at all before the smartphone spec arms race declares 1080p the new normal.