Weird mark behind the screen

Question

Weird mark behind the screen

Recently, I have noticed a weird mark on my screen.

Whenever my screen displays any black Pixels in the centre of the screen. This weird, barley visible, blue shape appears on my screen. To explain it better, when I look at this image http://tips4pc.com/wp-content/uploads/2010/05/black-screen2.gif I see the mark clearly, but when I move the image around my screen, the shape appears only when the image pases over where the shape is on the screen. The shape cant' be captured on screen capture, and when I turn my brightness all the way down or the screen off its not visible. The area of the screen where the shape is, displays other colours fine, its only noticeable when black pixels are displayed over it.

Its hard to explain and I will be happy to explain in more detail if you find it difficult to understand.

I just wondered if anyone else had a similar problem on Macbook Pros, a solution or any indication of what it might be.

I also wanted to ask (seeing as i'm in the display section), to connect my Macbook Pro to an HD TV, is it possible to buy a Mac --> HDMI cable which can has sound output as well? My current cable produces a good picture, but it can't take the sound from my mac --> TV. I have tried to use an audio out in the headphone slot, but it doesn't work.

Any help would be appreciated for either of these questions

Thanks

Alex

Mac book Pro 4GB vreesion 2.6 GHz, Mac OS X (10.6.6), 80G ipod

Posted on Jan 7, 2011 6:46 AM

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Answer 1

eww

Level 9

53,052 points

Jan 7, 2011 1:02 PM in response to Alexander Richardson

Alex, I suspect you're seeing light coming through the translucent Apple logo in the back of your MBP's display assembly. Put a hand behind the display and cover the logo (or position the machine so there's no light behind it) and see whether the "mark" disappears.

Yes, there are HDMI adapters that will carry audio as well as video from your MBP to your TV. Here's one:

http://store.apple.com/us/product/H1824ZM/A?mco=MTY3ODQ5OTY

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Answer 2

eww

Level 9

53,052 points

Feb 6, 2011 11:11 AM in response to Alexander Richardson

Your MBP 7,1 does output audio through its Mini-Displayport, but you may have an adapter that doesn't convey it to the HDMI cable. Some do; many do not. Here's one that does:

http://store.apple.com/us/product/H1824ZM/A?mco=MTY3ODQ5OTY

Are you suggesting I should use the cable to do further tests or to use it as an alternative to the screen.

Sorry, I don't understand the question. I'm suggesting that you replace your present Mini-Displayport-to-HDMI adapter with the one I've linked in this post, unless you're sure you have one that was advertised as supporting audio.

If instead of an adapter and a standard HDMI male-to-male cable you are using a single cable with a Mini-Displayport male plug on one end and an HDMI male plug on the other, that cable almost certainly doesn't support audio. An adapter that does, plus a standard HDMI cable, should give you better results.

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Answer 3

Jan 9, 2011 10:57 AM in response to eww

Hi eww

Thanks for your suggestion. It was a really creative solution, but unfortunately it wasn't the case. Its true that when the brightness (and therefore the apple logo) decreases, eventually so does the mark. But I tried it in dark conditions, covered the mark and discovered that the mark is actually to the left of where the light would shine through, its also a completely different shape. It was a good suggestion though.

Any other suggestions regarding the mark. Maybe I should take it in to the Apple Store.

regarding the cable, is there a cheaper alternative? i.e to buy a cable that just carries audio? If not then i'll probably buy what you suggested as it looks good and does the job.

Thanks once again for your help.

Alex

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Answer 4

eww

Level 9

53,052 points

Jan 9, 2011 12:29 PM in response to Alexander Richardson

How about posting a photo of the mark somewhere online and pasting a link to the photo into a post here, so we can see what you're talking about?

Pale marks on the LCD, visible only on a dark background, can be caused by excessive physical pressure on the outside of the closed display, but they have a characteristic shape that your mark may or may not match.

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Answer 5

Feb 5, 2011 5:47 PM in response to eww

I apologise for not getting back to you, its wrong to do so when someones offering help. I hope that you will still spare some time to help if you know the answer.

Here is the picture

http://img.skitch.com/20110206-nj2x4sqasmaijwex95qc5fidqs.jpg

Taken not very high quality but this is what I see on the screen. Hope you can make some use from it.
If not don't worry.
Thanks for your help

Alex

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Answer 6

eww

Level 9

53,052 points

Feb 5, 2011 6:11 PM in response to Alexander Richardson

The explanation Apple personnel have occasionally given for this mark (which has been reported and pictured here roughly two dozen times before, but which it seems that not all Apple Geniuses or technicians have seen or heard about) is that it's caused by undue pressure on the back of the display when it's closed — that is, it's user-caused damage. It has appeared after a user piled a big stack of books on his MBP or carried it in a briefcase or backpack and leaned against it. Some people have gotten it repaired under warranty because it wasn't identified as user damage; others have been refused warranty coverage because it was.

If you have a MBP that was made after April 2010, there is an audio signal emitted from its Mini-DisplayPort, and with a suitable MDP-HDMI adapter, you can transmit that signal to your TV set through your HDMI cable. If you have an earlier model, you can't get audio through the Mini-DisplayPort, but you can buy a special adapter that combines video from the MDP with audio from the headphone port or a USB port and sends them both to the TV via HDMI.

Look in System Profiler for your MBP's *Model Identifier* number and post it here. That will enable us to tell you which adapter you'll need to get.

Message was edited by: eww

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Answer 7

Feb 6, 2011 10:40 AM in response to eww

Thanks

I have an HDMI to Mini Display port , however audio doesn't work.

The Model Identifier number is MacBookPro7,1

Are you suggesting I should use the cable to do further tests or to use it as an alternative to the screen. I bought it in about August and I haven't got Apple Care Protection.

Thanks for your help.

Alex

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