What is this on my iMac screen? (photo inside)

[tkwolf]

I have the late 2012 27 inch iMac

i just noticed this now, check the bottom left of the pic, you'll a weird dack stain or something. I tried to press it but nothing, and I tried to wipe it but nothing. It seems to be inside the screen:

 

[boy-better-know]

I have the late 2012 27 inch iMac

i just noticed this now, check the bottom left of the pic, you'll a weird dack stain or something. I tried to press it but nothing, and I tried to wipe it but nothing. It seems to be inside the screen:

Image

I have exactly the same mark on my iMac 27" late 2012. It's been there for about 6 months. keep meaning to take it in and I will - luckily I have Apple care.

 

[Doga]

It is probably dust accumulating inside the LCD panel.

This past Summer I noticed the same thing all along the top menu bar on my late 2011 21.5" iMac. I removed the front glass thinking the accumulation was on the glass but no, it is under the frontmost layer of the LCD itself. Oh well, at least I gave the glass a good cleaning inside & out.

I was tempted to have Apple repair the screen but I decided to live with it as I'll be getting myself a new (non-retina) 27" iMac over the Christmas holidays.