"Moire" pattern on screen

So, it's not a "real" moire pattern, but it's like a grid of dots - no not pixels ...

I received a new 2015 15" MBP for my job and noticed that the screen has a "pattern" in the whites/greys - doesn't seem to cover the whole screen. It's not terrible but it's something that I notice. We had an old 2009 white MacBook that had this same issue. I've Googled the problem but never seen anyone else mentioning it - so maybe it's my eyes!

I have my own 15" that doesn't have this problem but I do notice an odd pattern in bright blue colors on it.

Are any of these patterns common problems?