S 7 Tab screen issue

I recently purchased S7 tab which is a pretty good tab. However, I noticed there is a color contrast across the screen one side of the screen has a slightly darker tint compared to the other side this will be obvious when opening a white page. I took it to the service center Axiom and the technician was able to acknowledge the issue but he had to take approval from Samsung before changing the screen. Later he called me and told me that Samsung has replied that this is normal and its a result of the "LED light lumination reflection" which I didnt understand and it doesn't make sense and they refused to repair it.