What's the scientific explanation behind temporary pink tint on Retina screens?

[cairene2011]

I've been observing temporary super-pink tints on both my iPad Mini Retina as well as my Retina Macbook Pro. This happens infrequently and I'm not bothered by it at all, as it always goes away by itself - but I'm incredibly curious what is behind it.

So what usually happens, is my iPad or rMBP are asleep, I wake them and sometimes - not always - for the first 5-10 minutes the displays are severely pink. The first time, I experienced it on my iPad mini retina at the airport. I had been reading on it in the cab the entire time, it was totally fine, all the whites were clean white. Arriving at the airport, I put it into its sleeve while making my way through security and pulled it out again at the gate, hoping to continue my reading. The moment I turned the screen back on, I was like ... all the whites on the screen were bright pink. I initially thought my eyes were playing a trick on me, since there was very bright natural light at the airport (windows all around the gates), but just holding a piece of paper next to iPad's screen showed clearly that there was indeed some pink madness going on. I turned the screen brightness up and down, turned the iPad off and on and off again ... the pink stuck. I put it back into my sleeve, thinking I'd deal with that "broken display" after my flight - when I pulled it out 3 hours later everything was back to normal and the whites were exactly as white as the paper sheets I used for reference.

Since then I had gotten this iPad mini replaced for an unrelated issue and also the new unit sometimes wows me for a couple minutes with extreme pink. Then it looks completely normal again.

Then, in January I got my rMBP and when I first switched it on, it had the same stark pink hue on the display in a bright room full of natural light. Even the Apple logo on the back glowed pink/purplish. I did the same "white balance" with a sheet of paper and my white walls and curtains to make sure it weren't my eyes playing a trick on me, but the screen definitely was super-pink. After a couple hours it went away and its whites matched the white of my walls and papers. Today, I woke up my rMBP and the pink veil was back on. After 10 minutes it was gone and all is well.

I'm not troubled by it at all (please don't think I came here to worry or complain, that's really not my intention), but I'm super curious to what is causing this?
Do the lights behind the retina displays not all come on simultaneously and the non-pink colours take a while to reach their full power? Like a classical neon-light that's dim and flickering for a couple of minutes till it becomes steady and bright? Or is it a matter of the light sensor getting overwhelmed in extremely bright natural light like a camera sensor that's struggling with the Auto White Balance?

If you know the mystery's solution, please share your wisdom with me!

 

[psingh01]

an "explanation" that was given for some iphones in the past was that there was some coating on the display that had not yet set which caused a yellowish tint. that it was "normal" and would eventually go away.

not sure if it has anything to do with what you are seeing but maybe it does.

my personal iphone 5 has always had a yellowish tint, even a replacement i got had it. i assume the white balance is off at least when compared to my iphone 4 which has a very white screen and imo superior. but it isn't enough to really bother me.

 

[cairene2011]

an "explanation" that was given for some iphones in the past was that there was some coating on the display that had not yet set which caused a yellowish tint. that it was "normal" and would eventually go away.

not sure if it has anything to do with what you are seeing but maybe it does.

my personal iphone 5 has always had a yellowish tint, even a replacement i got had it. i assume the white balance is off at least when compared to my iphone 4 which has a very white screen and imo superior. but it isn't enough to really bother me.

But if it was the coating, then presumably the tint wouldn't come back every few weeks once it has set for good?
Since I've seen it on all of my Retina devices (well, minus my trusty iPhone 5), I'm surprised no one else has experienced this. I've tried to google for it and there are a few people, who report pink/purple Apple logos, but most of them don't seem to have troubles with a temporary pink tint on the screen. The yellow tint seems to be a much more prominent issue, perhaps because it's more widespread or simply because it doesn't go away by itself.

Anyway, not the end of the world. If anyone has more ideas, keep 'em coming!

 

[sjinsjca]

an "explanation" that was given for some iphones in the past was that there was some coating on the display that had not yet set which caused a yellowish tint. that it was "normal" and would eventually go away.

The explanation I've heard and which IMHO makes the most sense is that it's an adhesive that takes a few weeks to fully cure. This seems sensible since the displays are complex, laminated structures. If the tint were due to an (external) coating then I'd expect it would vary more from place to place on the screen as the phone is used. Of course, it could be a coating on some internal surface. Either way: internal-surface coating or internal laminating adhesive, it fades over a short period, so it's nothing to be annoyed about.

Enjoy your fresh-and-new phone!

 

[cairene2011]

The explanation I've heard and which IMHO makes the most sense is that it's an adhesive that takes a few weeks to fully cure. This seems sensible since the displays are complex, laminated structures. If the tint were due to an (external) coating then I'd expect it would vary more from place to place on the screen as the phone is used. Of course, it could be a coating on some internal surface. Either way: internal-surface coating or internal laminating adhesive, it fades over a short period, so it's nothing to be annoyed about.

Enjoy your fresh-and-new phone!

That's really interesting, thank you for sharing! Do you also have a guess for my temporary pink tints?

 

[Freyqq]

That's really interesting, thank you for sharing! Do you also have a guess for my temporary pink tints?

Could be that the display is cold and heating up to its proper operating temperature? just a guess.

 

[cairene2011]

Could be that the display is cold and heating up to its proper operating temperature? just a guess.

When I think about it, it has never happened in a cold environment. That first airport encounter with the pink tint on my iPad mini was in July and my rMBP has yet to leave my central-heated apartment for the first time. I think temperature can be ruled out. Thanks for the suggestion!

 

[cairene2011]

So right now it's happening again - funnily I'm again at the airport. Here is a photo, brightness is on 100%.

Sorry the pic is upside down, on my phone it's the right way up - don't know why it's uploaded this way.

 

[John6Plus]

So right now it's happening again - funnily I'm again at the airport. Here is a photo, brightness is on 100%.

Sorry the pic is upside down, on my phone it's the right way up - don't know why it's uploaded this way.

That doesn't look right; it seems too even (and now long lasting) to be the curing adhesive, IMHO. It's always hard to judge a photo vs. how it looks in real life (BLUE DRESS). Would you say that photo is pretty representative (once you look at it on a normal screen)?

If it is accurate, it looks like someone who has their color temperature on their TV set too warm. There isn't a similar setting on an iPad, is there? The fact it's happening on two of your devices though, that's too strange.

I'm really no help.

 

[cairene2011]

That doesn't look right; it seems too even (and now long lasting) to be the curing adhesive, IMHO. It's always hard to judge a photo vs. how it looks in real life (BLUE DRESS). Would you say that photo is pretty representative (once you look at it on a normal screen)?

If it is accurate, it looks like someone who has their color temperature on their TV set too warm. There isn't a similar setting on an iPad, is there? The fact it's happening on two of your devices though, that's too strange.

I'm really no help.

Haha, I always saw blue&black.
I looked at the photo from my iPhone and my rMBP and yes, I think it is 98% colour accurate. In reality it is slightly deeper pink than it comes across on the photo, where it looks less intense and peachy. The too warm TV is a perfect analogy - I would describe it like this too.

I do think it is a software problem: Firstly, I had this effect on all of my 3 iPad mini retinas (those home buttons... thank god for Apple Care) AND on my rMBP over the course of the past year. Various environments, light situations, temperatures, hardware, etc.
Secondly, and most importantly, when I viewed the photo which I posted above on that very iPad mini retina, the whites of the bezel and the paper were still pictured correctly. However, once I would close the photo tab in the iPad's browser and look at the browser window/macrumors site/settings menu - you name it - whites were displayed pink again.

It's like the photo file told the iPad how to display the whites of the paper and the bezel correctly, but the rest of iOS tells it to display whites as pink.

It's a bit Inception-esque, but I hope what I said makes sense.