Mixed in among the larger and more ostentatious displays LG showed off at Display Week (like its beautiful 55-inch OLED TV) was a small, but important prototype: a 5-inch screen with a full 1920 x 1080 resolution. That's a whopping 440 pixels per inch, far beyond any other smartphone-class display on the market (or most other displays period, for that matter). Unfortunately, this display is strictly a prototype, at least at this point — it was simply a stunning display floating in glass, playing some pre-recorded video sequences. Along with the extremely high PPI count, the display also features a AH-IPS (advanced high-performance in-plane switching) technology for extreme viewing angles, though it wasn't easy to see that in action that due to the way the display was mounted. LG first announced this display last week, but seeing it up close certainly helps to drive home how insane this resolution is on a screen of this size. While we're not convinced yet that smartphones need to regularly exceed the 5-inch mark, there's no denying that this screen was a stunner — we're looking forward to the day when it arrives in a shipping handset.