Horizontal stripes on MBP Retina

Hi, I've read a few reports of this over the web but can't see it referred to here.

My Macbook Pro 15" (late 2013) is mainly used for photography editing. I look at images on it all the time and two days ago I noticed horizontal striping on nearly all blocks of colour. These horizontal stripes run across the whole screen and are more visible in some areas than others. It seems to be a physical problem as, if I take a screen grab and view on my iMac, it doesn't occur.

I've taken my trusty macro lens and photographed the fault. As you can see, it is quite apparent on the coloured buttons but also apparent in the more subtly coloured image to the left & the grey background. You can also see the lines running along the menu selection at the top if you look closely.

I've tried SMC resets, full reboot - all the usual 'magic fix' options I get when I call Apple support - looks like I may be sending this in for repair?