LG has announced it will be launching a new 5-inch LCD screen later this year, and that it will have a 1080p resolution and a pixel density of 440ppi, a marked improvement over the current range-topping screens.

Specifically designed for “smart devices,” LG’s screen uses AH-IPS technology — that’s Advanced High Performance In-Plane Switching, acronym fans — allowing a wide viewing angle, fast response times and a realistic color palette. The resolution is 1920 x 1080, which is more commonly found on HDTVs and high definition monitors, and the 5-inch panel will have a 16:9 ratio.

LG say it’s the first time full HD resolution will be possible on a smartphone, and it’s certainly an exciting proposition, however the 440ppi pixel density is equally as headline-grabbing.

Apple made a big deal over its Retina Display, with 330ppi, when it was introduced on the iPhone 4, and until now it hasn’t been significantly improved upon. LG’s press release says of the new 5-inch screen that “the naked eye is unable to distinguish between individual pixels.”

LG hasn’t announced a phone to accompany the new screen yet, but given its size, it’ll probably find a home on a tablet/smartphone hybrid, along the lines of the Galaxy Note and LG’s own Optimus Vu.

A sequel to the Vu is a possibility, as although there has been talk of an international release, it so far hasn’t strayed far from Korea. It’s doubtful that LG’s 4:3 ratio Vu could challenge Samsung’s Galaxy Note now anyway, given the head start it has had; but an Optimus Vu 2 with a 16:9 ratio, 5-inch,1080p screen could turn more than a few heads.

The screen will make its debut at a display trade show next week, and LG says it’ll be released during the second half of 2012. No doubt we’ll see Samsung’s response to it in the meantime.