According to a report on Android Police, a test conducted by them has discovered that the Nexus 7 tablets they had in hand has significant ghosting effects or image retention problem. Basically, image retention, is when you change from one on screen image to another, an impression of the the previous image is left over the current display.
According to Android Police’s test, when they left their Nexus 7 tablets at full brightness for 2 minutes, displaying an image and then pressed the Home button, they noticed severe ghosting effects on their device. The effects were noticeably lesser when automatic brightness was turned on.
“However, with the display set to automatic brightness, especially in sunlight, the problem is much less noticeable. But on maximum brightness or under incandescent/fluorescent light even on automatic, hovering over some icons for 5-10 seconds on your homescreen then swiping to an empty one will leave a very visible retained image for 10-15 seconds. Let me reiterate that: it’s noticeable even with things like homescreen icons on automatic brightness. You’ll have to look for it more, but it’s definitely there. I chose this example image because it’s the only one that’s really visible in a photo, it’s much harder to capture when it’s more subtle. The problem also becomes less severe the more time the display is on – it seems to “warm up.”
“Some have suggested this is a native behavior with IPS displays called “image retention.” I did a side-by-side of the same image with a Transformer Prime and Trasformer Pad 300 – both of which have IPS displays. The retention occurred only with a bright-white image on a darker color. The Nexus 7 does it with almost any image, and more severely. This may be an issue with the IPS panel in the Nexus 7, or it could be a software problem, but it’s by no means the same in every Android tablet with an IPS display out there. It’s definitely worse on the Nexus 7, any way you slice it.”
Asus has now responded regarding the matter and has issued a statement that states that they could not replicate the issue on production models.
So, as for now we believe that the ghosting issues are found only on pre production models – which Google I/O attendees received – and that too only on some units. The problem seems to been sorted out by the time Nexus 7 entered production stage.