Greyish Smudge marks behind the glass screen.

I have the same problem and as others say it's a design problem. But....how to get it fixed without paying for it when just 40 days out of warranty? Anyone suggestions?

Hello,
I have the same grey/dust spots almost the whole display after 2 months of use. As I read here and there, the problem is coming if you smoke close to the iMac or put glass of water/coffee etc near the computer. If the problem is coming from dirty air around, can it be fixed if you get out the display screen and seal it with something like silicone band or something like that just to protect the matrix from external dirty air? I can go and use my warranty to fix my problem, but it will come again after few months, so that's not the way, because when warranty expired, I must play on dusty crap screen forever. Can I put also something like strong fog filter in back of the iMac, where the fan is? I just want to find a solution about that problem, not just a temporary fix.

Add me to the list. My 2009 27 inch iMac was purchased brand new in December 2010 still sealed in the box. It's been used for three months and the grey smudge marks are beginning to appear in the two top corners and along the right side. I have a single layer of unscented dryer sheets taped over all the visible intake vents. I've used them for years to keep dust etc. out of my computers and this works extremely well. I've opened up cases that were shut for over a year and they were clean as a whistle. Dust stays out and there is no negative effect on cooling. However, this has not prevented the smudge marks from appearing.

If it was dust, smoke, pollen, whatever, it would be on the outside of the glass too. Also, if you clean it off with a white cloth, smoke would be very orange/yellow, not grey. Coffee "fumes" would not be grey either. Pollen would be yellow. My homemade filters are clean, but the inside of my LCD is not. I think it is possible that the offending matter, whatever it is, is being generated from INSIDE the iMac. Don't get me wrong...I love my new Apple products, but this is unacceptable, especially if the marks continue to grow, eventually affecting the entire display.

I was thinking about using the dryer sheet idea. I have had two screen replacements and one power supply replacement. My newest screen has already developed symptoms, had it replaced in Jan 2011. My first replacement screen was the worst as I had to change it with 3 weeks. The spots where everywhere that quick! My current screen has a big spot (larger than a quarter) and about three smaller ones in the the right hand corner. The spots seem to start there with every screen. Well the first replacement they grew dow the middle. The largest spot is not growing but is located where the GPU heat pipes end. Maybe it is due to the GPU? I had a g5 imac for over four years same location that sill has a flawless screen. This can't be blames on the environment! I am waiting to have this one fixed, if at all. The smaller spots are growing but not nearly as fast as the first two screens I went through. I really love this machine and it kills me on the inside that this is happening.
Apple solved my question on if I needed to buy more of these for my small business. Why pay more if you have to go to the apple store every 5 weeks! I really wanted to go with apple for my business needs but I am can't justify it at this point. I hope this helps. I really want to figure out how to fix this. Sorry for the long post.
Thanks

My 2009 27 iMac had its screen replaced once, I had to call Applecare directly because I was refused by the official service center because the Apple tech told me that it was due to "environmental problems." Anyway got the screen replaced anyway after pleading to Applecare. So far so good but I noticed some friends of mine who also have the glass and aluminum iMacs also develop the same problems. I sure hope that Apple would acknowledge this problem because there is indeed a design flaw here.

I'm not sure if I have the same issue here... This looks like some strange screen artifact and I noticed it after I installed Firefox 4... I closed out of the program and put a DVD in and I noticed this 1" or so vertical line where the edge of my Firefox window would have been, just at the top. No other smudges/artifacts that I can detect thus far. I had to take a photo with my phone as it wouldn't show up on a screen shot!

Picture - mouse pointer shows the line. http://i15.photobucket.com/albums/a399/nerfderfy/IMG_0503.jpg

Is this the same issue? This is a 2010 iMac, 21.5"

Nope, not the same issue. The smudges are actually on the glass. That looks like an artifact of some sort on yours. The problem this thread is about refers to marks visible even when the machine is off.

Purchased iMac 21.5-inch in mid-February 2011. This week, March 28th week, within six short weeks, the HD began failing. (Disk Utility report: S.M.A.R.T. Status: Failing -- "This drive has a hardware problem that can't be repaired.") When the HD began failing, several-inches in diameter "smudge" in upper right-hand screen corner and inches-long streaks of "smudges" running from left corner top to mid-screen. After this disappointing iMac experience, I don't expect to purchase another Apple computer.

The spot on my system are not on the glass. They seem to be between the LCD and Backlight. If they were just on the glass I would have cleaned it myself.

I got mine back today after 2 weeks of 'diagnostics' with a brand new screen. It looks lovely now, but for how long I wonder...

Mine look like they are on the glass but that could be an illusion. Are you saying if I pop the glass off I still can't get to whatever these things are? They've gotten bigger in the last week! They sort of fan out and look like they are being expanded by airflow.

Xav8tor,
I thought the same thing as well, however I did some googling and discovered that many people couldn't clean the screen unless they separated the LCD from the backlight. http://www.flickr.com/photos/61503983@N08/5593711718/
this is a picture of just one of mine on current screen. You can see the big one with faint clods growing around it. FYI I have an Air purifier (HEPA) in my office going 24 / 7.

This caused me to take a closer look. If i put an image of a line ( or something simple) over the spot, I can see that the image on the screen appears over the spot not the spot over the line.
Hope this helps.

Message was edited by: Christopher G.

Same for me on my early 2010 iMac: the greyish marks started to appear 3 months before the end of 1-year warranty but they were minor. Now, three months after the end of the 1-year warranty, they have spread about 1/3 of the screen.

I'm going to try the European 2-year warranty and the hidden defect. Cost for Apple is minor since it could invoice its supplier.

French iMac Alu 24" 3.06 Ghz Early 2009 : Same greyish smudges on top of screen 😟

French iMac 27 october 2009

I can not go ... I have Apple Care and I have already changed 3 times the LCD panel for spots on screen + graphics card + power supply ... Apple if you hear me ... I want a refund ... Very disappointed