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Many high-end flagships are already making use of higher resolution QHD (2560×1440) displays, but it seems increasingly likely that we will see our first 4K display smartphone before too long. Sharp, a Japanese LCD display manufacturer, has just announced its 5.5-inch 4K (3840×2160) IGZO display, which packs in a ridiculous 806 pixels per inch.

For comparison, QHD smartphones like the Samsung Galaxy S6, LG G3, and Nexus 6 feature a PPI of 577, 538 and 493 respectively. 1080p smartphones are a little lower at 441 PPI for the HTC One M9, 424 for the Sony Xperia Z3 and 401 PPI for the larger OnePlus One. Of course, the important question is whether or not there’s any benefit to consumers in designing devices with such small 4K displays. The consensus is that the move from 1080p to 2K offers only minor visual benefits, so 4K will surely be even less noticeable.

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However, native support for increasingly common 4K content may be a nice feature to have and would be supported by advances in mobile video capture and playback technologies. Furthermore, the recent rise of virtual reality headsets may give a boost to such small 4K displays, as the viewing distances are even closer than typical mobile applications and therefore require ultra-sharp images.

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IGZO stands for indium gallium zinc oxide and is the material used in the backplane of Sharp’s display. This material is partly what has allowed Sharp to increase its pixel density so rapidly, as it has a higher electron mobility than a-Si, an essential property as backplane transistor sizes shrink down further. Sharp states that its 5.5-inch 4K IGZO panel will go into mass production in 2016, with smartphones as the most likely target market.

Sharp’s mobile display business has been struggling for profits over the past few years. The company is rumored to be looking for additional funding from the Innovation Network Corp. of Japan and may spin off its mobile LCD business as part of a deal. Do you think that the race to small form factor 4K displays will pay off for Sharp?