I've seen this on many LCD displays. And the colors shift as you move viewing angles. It's a shame there is no course today on what is and how does LCD technology works and how such things show up. The technology involved is a dance between costs and perfection.
Whenever there is a white HD screen on my PN58C7000, there are certain areas of the screen where some of the pixels have a purple tint / flicker to them. This does not happen when I do the black/white rolling screen test built in the tv. This only happens when the screen is solid white. Any other type of picture is perfectly fine. TV, movies, video games look great. This is a minor annoyance and I am curious if anyone else has this problem.