Take the 2-minute tour ×
Ask Different is a question and answer site for power users of Apple hardware and software. It's 100% free, no registration required.

My 13" MacBook Air (late-2010 model) shows strong flicker on some of the following "Inversion / Pixel Walk" test images from the LCD test on the site "lagom.nl". Does that truly indicate a quality problem with the screen (as the test says), or is it a normal side effect from the screen technology that any 13" MacBook Air would suffer from?

I do notice that when scrolling say a web page or Pages document, the image noticeably flickers while scrolling. This might be due to the problem this test is supposed to detect, but I'm not sure. Web pages with a striped background where the stripes are just 1 pixel high also show annoying flicker (even when not scrolling).

The test images: http://www.lagom.nl/lcd-test/inversion.php#inversion-all.png

At full screen brightness on my 13" Air, I can see strong flickering on test image 3. Some of the other images show some slight flickering too, but 3 is particularly strong. By "strong" I mean that the flicker is clearly visible even from over 1.5 meters away from the screen (and yes I measured that).

I had a chance to test it out on two store models of the 13" MacBook Air and couldn't see any strong flicker, but I did forget to turn up the screen brightness so I'm not sure. Neither my 20" Cinema Display nor some MacBook (Pro) and PowerBook screens I tested showed any strong flicker. But note that the Air's screen has a higher pixel density, could that affect this test?

And if it's a quality problem, is it something I should / can demand Apple to fix or replace? (I still have a few days of return period left; it might just be a minor nuisance, but do I have to put up with that considering the price of the machine? ...)

share|improve this question
add comment

3 Answers 3

up vote 0 down vote accepted

The flicker is caused by the technology (TN) used in your MBA. It's noticeable when brightness is high and under some of the tests. I have 13" MBP 2010 and I can register flicker on 2a and 4a tests when brightness is above 50%.

Usually under normal use this shouldn't be noticeable.

share|improve this answer
    
Thanks for the response. I did in the end ask for a replacement, and got one. On the new machine, the test shows very slight flicker on pattern 4b, but nothing like the first machine. I haven't experienced any vision issues with it in day-to-day use, with the exception of the striped background used on insidemacgames.com which does exhibit noticeable flicker. –  Rinzwind Aug 3 '11 at 20:00
add comment

Every Mac I've ever owned does this same thing. Don't demand a replacement.

As an aside, monitor flicker is sometimes noticeable because the 60Hz refresh rate is the same frequency as house electrical current. This causes your lights to blink at that rate. This is usually imperceptible, but can be noticeable with a monitor if they get synced up. This is more common with CRTs, but not unheard of with an LCD.

Don't worry yourself over this. Did you notice problems with your display before the test?

share|improve this answer
    
Yes, I had some headache / vision trouble with the screen the first few days of use so I went looking for an explanation and stumbled upon this test. I thought perhaps the very strong flicker I was seeing in the test images was also showing up in normal images, albeit weaker but still noticeable. I don't know if that makes sense, as the explanation given with the test is that the flicker would show up in normal use mostly in moving images (as when you scroll), not so much in static ones (except for weird website backgrounds that look like the test image). (continued in next comment) –  Rinzwind Jan 4 '11 at 21:33
    
(continued from previous comment) I do seem to have adjusted better to the screen by now. But I still have the sense that the screen shows flicker. I must admit this may be totally subjective as others didn't really see a problem, so it's hard to ask Apple to do anything about it. To be clear: everyone immediately sees the flicker in the test image, so if this is enough of an objective reason to think there might be a quality problem with the screen that can be solved; it might make sense for me to try to get it repaired or replaced. –  Rinzwind Jan 4 '11 at 21:33
    
Not true. Half of the world uses 50Hz AC, and the notebook uses DC power. AC caused flicker is usually caused by the high voltage convertors in bad CRTs. The Flicker @rinzwind describes is because of the TFT technology used. –  mspasov Aug 2 '11 at 8:51
add comment

As noted by others, the amount of pixel walk varies from screen to screen, even in the same model. My experience is that this has nothing to do with it being a TN panel as IPS screens get pixel walk, too.

If it is noticeable on solid colors, I would consider it defective. Especially if you have one display that is noticeably (i.e. your non-technical uncle or other disinterested party would agree that one of the several identical models was "off" upon a casual demonstration of normal use. Basically, a one minute test with identical web browsers up - ask the "helper" if they all look the same when scrolling). When something is made that different than another model, seeking an exchange from the manufacturer seems like a reasonable request.

share|improve this answer
add comment

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.