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tigress666

macrumors 68040
Original poster
Apr 14, 2010
3,288
17
Washington State
So, I just got a clock app for my iPhone that has a really nice interface and I'd like to use it as my clock at night.

My roommate says if I leave it on all night like that (the clock has an option to keep the iphone from screen saving) I'll burn out the back light part quicker.

I noticed the clock has a feature that you can dim the display by swiping it and it appears you can dim it to the point of no display (like when you put the dim switch to 0)? I just looked closely and it does still display a little bit but you can't tell unless you look closely (Even at night) it's so dim.

Anyways, I'm wondering if I kept it that dim (except for swiping it when I wanted to look at it), would that be much of a toll on the backlighting on the phone?

And how many of you who have had iphones for a while use yours as a clock regularly and have you had issues with the backlight burning out?
 
So, I just got a clock app for my iPhone that has a really nice interface and I'd like to use it as my clock at night.

My roommate says if I leave it on all night like that (the clock has an option to keep the iphone from screen saving) I'll burn out the back light part quicker.

I noticed the clock has a feature that you can dim the display by swiping it and it appears you can dim it to the point of no display (like when you put the dim switch to 0)? I just looked closely and it does still display a little bit but you can't tell unless you look closely (Even at night) it's so dim.

Anyways, I'm wondering if I kept it that dim (except for swiping it when I wanted to look at it), would that be much of a toll on the backlighting on the phone?

And how many of you who have had iphones for a while use yours as a clock regularly and have you had issues with the backlight burning out?

Hi,

Not sure about that. I shouldn't think that it would burn out the backlight - it's similar tech to an LCD TV isn't it? And I don't think anything of having my TV on for long periods. Sure the backlight will have a finite lifespan, but I would imagine it's quite a long time.

As for the app, I don't think Apple currently allows apps to access and adjust the actual backlight brightness - the 'dimming' feature on clock apps I've used in the past (trying to find something for the same purpose) has just dimmed the colour down to something closer to black, but it will still glow quite alot because the backlight hasn't actually dimmed at all - which is why I don't use my iPhone as a bedside clock. And I think I've tried most of the alarm clock apps!
 
Hi,

Not sure about that. I shouldn't think that it would burn out the backlight - it's similar tech to an LCD TV isn't it? And I don't think anything of having my TV on for long periods. Sure the backlight will have a finite lifespan, but I would imagine it's quite a long time.

As for the app, I don't think Apple currently allows apps to access and adjust the actual backlight brightness - the 'dimming' feature on clock apps I've used in the past (trying to find something for the same purpose) has just dimmed the colour down to something closer to black, but it will still glow quite alot because the backlight hasn't actually dimmed at all - which is why I don't use my iPhone as a bedside clock. And I think I've tried most of the alarm clock apps!

I dunno, adjusting the dimmer seems to work cause I can't sleep with it at full bright but dim it some and it is fine.

As I said, when you dim it all the way at night, you can't even tell the screen is on. I just noticed today looking at it closely that I could barely tell out the numbers. Plus, in daylight mode (where it has a grey background with black letters, it is trying to imitate a basic digital clock), if you dim it all the way you can't tell it is on at all (you can't make out any letters but maybe that's cause they stay black while in night mode they are color of your choice on a black background). It seems to actually get dimmer than if you adjust the brightness to all the way 0 in settings on the iphone (but that may be because Apple doesn't want you to be able to go the dimmest the phone can get cause then you wouldn't be able to see the screen even to unset the dimness). And I just discovered if you set the phone to the dimmest brightness in settings, and then tell the clock to go to its dimmest, even in night mode you can't see anything on the screen anymore, it looks completely off.
 
I dunno, adjusting the dimmer seems to work cause I can't sleep with it at full bright but dim it some and it is fine.

As I said, when you dim it all the way at night, you can't even tell the screen is on. I just noticed today looking at it closely that I could barely tell out the numbers. Plus, in daylight mode (where it has a grey background with black letters, it is trying to imitate a basic digital clock), if you dim it all the way you can't tell it is on at all (you can't make out any letters but maybe that's cause they stay black while in night mode they are color of your choice on a black background). It seems to actually get dimmer than if you adjust the brightness to all the way 0 in settings on the iphone (but that may be because Apple doesn't want you to be able to go the dimmest the phone can get cause then you wouldn't be able to see the screen even to unset the dimness). And I just discovered if you set the phone to the dimmest brightness in settings, and then tell the clock to go to its dimmest, even in night mode you can't see anything on the screen anymore, it looks completely off.

Just in case you've found the only app which does actually dim the backlight, can you tell me which app you are using please, I'll give it a whirl! :p
 
It is a common myth that LCD's can't get burn in, also the back lights do get dimmer the more you use them. Thing is it is a VERY long time to do either on an LCD and I am really not sure if certain types of LCD's are more prone to burn in or some reject it completely.

None the less the LCD on my 3Gs when I got it had some burn in, was pretty hard to see but you could notice it on movies and when scrolling thing, also visible on an all white screen of course. Super easy to get a new LCD and backlight on the 3Gs so I just did that.
 
Just in case you've found the only app which does actually dim the backlight, can you tell me which app you are using please, I'll give it a whirl! :p

Mighty Clock. Though I do notice if you don't have the phone itself at the dimmest settings when you turn it off when Mighty Clock is at its dimmest you do notice a slight change in the screen (you can see it turn off).

It really doesn't put out any light though that is tellable (save the actual numbers lighting up) when it is at its dimmest. At least in my opinion.
 
No worries, the MTBF (mean time between failures) is thousands of hours.

Enjoy :)

1000 hours is just four month if you let the app on every night for the entire night. I assume you sleep 8 hours per night.

Your post is not reassuring at all. It is actually scaring the hell out of me. Hopefully, you don't know what you're talking about and the MTBF is more like tens of thousands of hours or hundreds ;-)
 

I thought backlight dimming over time was an issue more for old CCFL backlights (on computers, not phones) than for LED backlights (which phones have always used). Certainly lots of LEDs like the ones use for power lights have very long uptimes (eg my TV has a logo that is lit red when its off and blue when its on -- its been running in one color or another aince 2006).

A search does suggest people have their backlights fail on the iPhone, although I don't know that it's common (I've never had a cellphone backlight fail, but I've never had a cellphone fail, either).
 
1000 hours is just four month if you let the app on every night for the entire night. I assume you sleep 8 hours per night.

The oft-quoted MTBF for most LEDs tens to be on the order of 100,000 hours. So if the rating holds, on average it would take a little over 11 years of constant display lighting to have a problem.

There have been actual tests done on LEDs to asses their performance. It shows that MTBFs can actually be quite a lot longer, and the worst that often happens is, you get a slowly declining light output that gets to about a 25% reduction at 5,000 hours (roughly 6 years of use).

Or put another way: chances are, the 2G, 3G, WiFi and Bluteooth standards that the iPhone 4S uses would probably be long gone before you'd even have to worry much about the display going, let alone a lot of other components that would be likely to fail way sooner.

That said, displays have been known to go out on lots of devices with LED backlights, but that's usually due to defect, abuse, damage or some other component (the GPU, logic board, some LCD issue or a connector) failing. In other words: it's not likely that keeping he display lit had much of anything to do with those failures.

Your post is not reassuring at all. It is actually scaring the hell out of me. Hopefully, you don't know what you're talking about and the MTBF is more like tens of thousands of hours or hundreds ;-)

There's no need to be scared. It's just a phone, with a warranty. If you're that worried about it, get Applecare.
 
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The MTBF for most LEDs tens to be on the order of 100,000 hours or longer. So if the rating holds, on average it would take a little over 11 years of constant display lighting to have a problem.
Is the iPhone backlight made out of LEDs? And even if it is, there are much more than the light emitting component at play here...

That said, displays have been known to go out on lots of devices with LED backlights, but that's usually due to defect, abuse, damage or some other component (the GPU, logic board, some LCD issue or a connector) failing. In other words: it's not likely that keeping he display lit had much of anything to do with those failures.
I have an original iPhone (Edge version) that has backlight issues. It still works, but the backlight is now very uneven. Or maybe it's the LCD screen, I can't really tell. In any case, I don't know if it's the long exposure that is responsible... Actually, my wife had one and the screen looks perfectly fine, so that's probably a defect of some sort.
There's no need to be scared. It's just a phone, with a warranty. If you're that worried about it, get Applecare.

The warranty does wear off after a while. I don't want to use my iPhone in a way that'll let it "damaged" in a couple of years, log after the warranty has expired.

Anyways, thanks for you answer.
 
Is the iPhone backlight made out of LEDs? And even if it is, there are much more than the light emitting component at play here...

Yes, they are made of LEDs. And I already mentioned that the there are indeed lots of other components that need to be worried about, but if they fail, it probably won't be because you had your screen turned on all the time.

Lets put this another way: there are lots of LED-display or LED-backlit alarm clocks, indicator panels and automotive instrument clusters. A lot of them run the LEDs all the time they're being used. In the case of alarm clocks, it's 24/7. And it doesn't seem to be that much of a problem.


The warranty does wear off after a while. I don't want to use my iPhone in a way that'll let it "damaged" in a couple of years, log after the warranty has expired.

just using your iPhone at all subjects it to risk of "damage." If you obsess over what MAY fail on your iPhone so much that it prevents you from doing what you want, you may as well just leave it sitting, pristine in its box, never used...


... except even that risks "damage" in that it's not good to keep a Lithium Polymer battery in a disused state for a prolonged period.

Your devices are going to wear over time. Just use them.
 
As late as 2001 and probably past that for a few years, handhelds used CCFL backlights because they were less expensive and used less power.

(I personally changed the backlight tube in my Jornada 560. Tiniest thing.)

The iPhone and other smartphones all now use LED backlighting with a life of 50,000 hours or far more.
 
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Your roommate is right, however LEDs have such a ridiculously long burn time that you are likely going to get rid of the phone before this happens.

I had an old acer LCD monitor from about six years ago. It ran for likely 8-10 hours a day and just want out. However, it went out completely. There are multiple backlights in those screens so I don't even specifically suspect it being burnout but rather some other circuitry issue.
 
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Your iPhone screen will burn out after 5 years, 8 months, and 15 days of continual usage. The clock is ticking! Better start saving up for a new iPhone!!! :eek:
 
I know we're talking about the iPhone here. However I assume the same goes for the iPad 2?

I use the same app on my iPad 2 - I assume due to it's LED screen, I won't have any issues sung the clock all the time?
 
I know we're talking about the iPhone here. However I assume the same goes for the iPad 2?

Yes, generally speaking. Like the iPhone (and pretty much all new cell phones and most new computers or monitors), all iPads of all generations have an LCD with an LED backlight (no iPad or iPhone has an LED screen, and it's not clear when/if Apple will jump to that technology).
 
lolwut?

Why dont you just close it, when you need to use it just press the home button/power button and see the time.

It'll defiantly cause damage to your battery and screen using it 24/7.

Or just buy a $5 clock from like Walmart or something.
 
Nightstand Central

"Just in case you've found the only app which does actually dim the backlight, can you tell me which app you are using please, I'll give it a whirl! :p"

I believe Nightstand Central does. I used it for 8 hours or more every night with my 3GS and continue to do so with my 4S. (I don't sleep that much - no such luck, but it's useful to have the clock sitting there.) You can set different backgrounds which change with a frequency you set. I have some of my photos (pretty dark mud patterns with water reflections) alternating with their image options. It's a beautiful app; you can set different alarms too (your music or Apple's options). I just checked and it's still in the iTunes store. This thread worries me, but I haven't heard anything elsewhere about burn-in.
 
The question is, why don't you just get an alarm clock? Unless you randomly wake up in the middle of the night to play with a 'nice user interface'
 
@irDigital0l, @daaneel

I could buy an alarm clock. But then again, I have one built in my iPhone, so why should I bother?

@Prof. @scaredpoet
Your posts are appalling. If overusing some feature is going to wear out my screen after a year or two, I want to know. As daaneel and irDigital0l just mentioned, there are good alarm clocks for 10€ about just everywhere. So I'd rather buy one of these than wear out my €850 iPhone too quickly. It's simple enough economics, I don't think I have to explain.

Now, if my iPhone is perfectly capable of replacing an alarm clock with no noticeable drawbacks, then I'm in.

You people need to open up a little. Just because you don't see the purpose of some question or some usage of an iPhone doesn't necessarily mean the party thinking/asking it is a crazy bum.
 
@irDigital0l, @daaneel

I could buy an alarm clock. But then again, I have one built in my iPhone, so why should I bother?

@Prof. @scaredpoet
Your posts are appalling. If overusing some feature is going to wear out my screen after a year or two, I want to know. As daaneel and irDigital0l just mentioned, there are good alarm clocks for 10€ about just everywhere. So I'd rather buy one of these than wear out my €850 iPhone too quickly. It's simple enough economics, I don't think I have to explain.

Now, if my iPhone is perfectly capable of replacing an alarm clock with no noticeable drawbacks, then I'm in.

You people need to open up a little. Just because you don't see the purpose of some question or some usage of an iPhone doesn't necessarily mean the party thinking/asking it is a crazy bum.

When I push my home button I see the time displayed at the top of the screen. You can also use the built in OEM alarm function to wake you up. ALL of this with out using the back light all night long!

Now, who is being crazy?:eek:
 
When I push my home button I see the time displayed at the top of the screen. You can also use the built in OEM alarm function to wake you up. ALL of this with out using the back light all night long!

Now, who is being crazy?:eek:

So I guess all people that don't share your view of things are crazy then. Since YOU feel I don't need it, it's obvious I'm the crazy one. But that makes you the obtuse one.

Yes, I don't need this. I've lived happily until now without having an alarm clock displaying time on sight. Yes, it's a gimmick. So what? I should not consider it because you don't need it?

I'll try to explain then, since it looks so alien to you. As it turns out, I have trouble sleeping. I have a very very light sleep. As a result, I wake up between 2 and 5 times a night on average. I usually don't have trouble getting back to sleep, but I like to look at the time to see if it is worth getting back to sleep, since I often wake up 5 minutes before my alarm clock. And of course, the less I move and the less I use my brain, the better the chance of getting back to sleep.

To get the time, I can move my arm, click on a button (with the random chance of the iPhone falling down) and be blinded by the maximum luminosity of the locked screen. But this alone is sometimes enough to wake me up for good, especially if the iPhone falls down and I have to pick it up on the floor.

Just having to turn my head and read the time on a very dim screen (I turn luminosity to the minimum both in the app and in settings before going to sleep) if *much* less intrusive. It actually is pleasant and I consider it a bonus.

There, now you know it all about my craziness.
 
So I guess all people that don't share your view of things are crazy then. Since YOU feel I don't need it, it's obvious I'm the crazy one. But that makes you the obtuse one.

Yes, I don't need this. I've lived happily until now without having an alarm clock displaying time on sight. Yes, it's a gimmick. So what? I should not consider it because you don't need it?

I'll try to explain then, since it looks so alien to you. As it turns out, I have trouble sleeping. I have a very very light sleep. As a result, I wake up between 2 and 5 times a night on average. I usually don't have trouble getting back to sleep, but I like to look at the time to see if it is worth getting back to sleep, since I often wake up 5 minutes before my alarm clock. And of course, the less I move and the less I use my brain, the better the chance of getting back to sleep.

To get the time, I can move my arm, click on a button (with the random chance of the iPhone falling down) and be blinded by the maximum luminosity of the locked screen. But this alone is sometimes enough to wake me up for good, especially if the iPhone falls down and I have to pick it up on the floor.

Just having to turn my head and read the time on a very dim screen (I turn luminosity to the minimum both in the app and in settings before going to sleep) if *much* less intrusive. It actually is pleasant and I consider it a bonus.

There, now you know it all about my craziness.

Sir I believe to minimize intrusiveness, you should mount an iPad to your ceiling with a bluetooth remote control in order to set your alarms and whatnot THAT WAY you don't even have to turn your head! If you sleep on your side then you should get TWO iPhones and put them on both sides of the bed!

Now I know this is all 'alien' to you, but you really need to stop being obtuse
 
Sir I believe to minimize intrusiveness, you should mount an iPad to your ceiling with a bluetooth remote control in order to set your alarms and whatnot THAT WAY you don't even have to turn your head! If you sleep on your side then you should get TWO iPhones and put them on both sides of the bed!

Now I know this is all 'alien' to you, but you really need to stop being obtuse

:D Now that was funny!
 
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