Acer was the first manufacturer to present a full HD tablet at CES 2012 earlier this year; the 10-inch Iconia Tab has a 1920x1080 pixel display with a pixel density of 220ppi, almost 50 per cent more compared to the current crop of Android tablets.
There have been a number of reports in the last few months that hinted that Apple could release a 2048x1536 pixel resolution (264 pixels per inch) and it now appears to be much more likely to happen as the company would try to surpass its rivals.
In addition, there are rumours that Samsung's successor for the Galaxy Tab 10.1-inch tablet could have a 11.6-inch screen with 2560x1440 pixels or a pixel density of 253ppi and Lenovo will launch a tablet with a similar resolution.
Apple is claimed to have enlisted one of its rivals, Samsung Electronics, LG Display and Sharp Electronics to produce that QXGA panel. That said, whether Apple will stick to the "retina display" nomenclature remains to be seen.
iPhone 4's screen has 330 pixels per inch pixel density and Apple would actually have to produce a screen with a 2560x1920 pixel resolution (that's nearly five megapixels) in order to live up to the iPhone 4's "retina display" specs.