Strange marks on my iMac 27" screen

Question

Strange marks on my iMac 27" screen

So, I just discovered some strange marks in the lower corners of my iMac 27" screen. The computer is almost exactly one year old now. They are not dirt, I've tried cleaning the screen but they seem to be "behind" the outer plastic. They are mostly visible on light areas. Attached image shows them on a light grey plain area. Any ideas what they might be and how to get rid of them? I've got similar but not so apparent marks on the lower right corner as well.

iMac 27", macOS 10.15

Posted on Apr 14, 2020 5:02 AM

Reply

Answer 1

rkaufmann87

Level 10

148,452 points

Apr 14, 2020 6:44 AM in response to PerzecSquared

First please ensure the computer does not have image persistence by following the instructions in Avoiding image persistence on Apple displays.

However if the Image Persistence is not the issue please contact AppleCare using the following link: AppleCare Contact Info

Reply

Answer 2

BDAqua

Level 10

250,253 points

Apr 15, 2020 9:29 AM in response to PerzecSquared

It's dust...

https://forums.macrumors.com/threads/did-you-know-about-dust-problem-in-27-imac.2122476/

Reply

Answer 3

Apr 23, 2020 10:31 AM in response to PerzecSquared

Well, I just got the computer back and I don't know exactly what was wrong, but they actually changed the whole screen so they didn't settle for blowing away some dust. So, unfortunately I don't know for sure what was wrong with it.

Reply

Answer 4

Apr 16, 2020 12:46 AM in response to BDAqua

Hm, you might be right in that it's dust, it sure looks an awful lot like it. I guess I'll know for sure on like Monday, when I'm leaving it in the shop to get looked at. I'll get back to you. Never heard of it happening to the 2019 models though.

Reply

Answer 5

BDAqua

Level 10

250,253 points

Apr 23, 2020 10:48 AM in response to PerzecSquared

OK, thanks & good luck! :)

Reply

Answer 6

Apr 15, 2020 12:28 AM in response to rkaufmann87

I've tried the first option, and it doesn't seem to be image persistence.

In fact, what I have found is that the spots seem to be "polarised", in that if I stand up and look from above, they more or less disappear and in fact turn lighter than the background instead of darker. My guess is that it's some kind of strain in the plastic, either in the cover or in the actual LED panel, producing this effect. I've been in contact with Apple support now, and I am going to leave this at a shop on Monday to get it fixed. Since it turned one year just two weeks before this appeared, I will have to go by Swedish consumer laws (mandating a hardware guarantee for three years) instead of the regular Apple Care package.

Reply

Strange marks on my iMac 27" screen

Similar questions