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Hardware

Extending LCD Display Life? 25

Posted by Cliff from the leave-it-on-or-turn-it-off dept.
polymath69 asks: "I use a laptop as my primary home machine, and wish the display to last as long as possible. There are two main camps of opinion on how one ought to ensure this, each grounded on a seemingly logical point. Opinion One goes like this: An LCD's backlight is only going to emit photons for some number of hours, therefore shut it off when not in use to maximize life. Opinion Two counters: A backlight can only be turned on some number of times, therefore leave it on to maximize life. The conclusions in each camp are diametrically opposed. So what is the truth? And how do you make a choice when two seemingly irrefutable arguments are in disagreement? Both these truths start from the same given: that eventually, the LCD will fail. But looking at that given from two points of view leads to contradictory answers. Now, one of these arguments has got to prevail. But which is it, and why?"
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Extending LCD Display Life? More

Extending LCD Display Life?

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  • wandering rapidly off-topic...

    My no-name laptop only has two mouse-buttons, but has the undocumented feature that the touchpad recognizes a tap with two fingers as being a click of the middle mouse-button, and a tap with three as being the right mouse-button. Since I prefer tapping the pad to pressing buttons, it works fine - I never have to press buttons.

    Touchpads made by Synaptics can be configured so that the left physical button acts as middle button - to left-click, you tap, to middle-click, you press the left button, and to right-click, you press the right button. There's a link to the appropriate program (tpconfig, IIRC) from Synaptics' web site.
  • Seems like you haven't taken a look at the IBM ThinkPad line, every single ThinkPad has 3 buttons. That and the fact that everything in it is Linux Friendly hardware was the reason I purchased a ThinkPad A20M last Oct. They may sound a bit pricey, but this is IBM we're talking about here and you _do_ get what you pay for. The college I go to got an offer from HP to buy brand new XE-3's (before they hit the general market) at a lowlow price, I'm glad I waited because after a while the LCD went bonkers on most machines but my ThinkPad has been chugging along ever since.
  • My thinkpad A20m works great in Linux...
    It's got 3 mouse buttons, and the internal modem works fine with the ltmodem driver from linmodems.org. I didn't opt for the internal ethernet, instead I use a Netgear FA510 10/100 PCMCIA card.
    The built in sound originally required the ALSA drivers from www.alsa-project.org, but I think the later kernels have support for it.
    If you pick the right model thinkpad, you can even get Linux preinstalled on it.

    Even APM works, including suspend and hibernate.

    I'm not too worried about the LCD backlight wearing out... Not for a few years, after which I'll probably need a new computer with a bigger drive to accommodate my files ever increasing size and entrophy.
  • Umm... a couple weeks back... the Latitude belonging to another employee here had a backlight failure... the display worked in that if you looked really hard you could see the picture, but there was no way to use the system, the LCD was practically black (dark dark grey)...
  • My experience is that the inverter for the backlight will die far sooner then the backlight itself. Some poorly designed laptops are more prone to this then others. Turning the laptop on is usually what kills the inverter, but since you can replace the inverter for cheaper then the screen, you may want to turn off the display when not in use... I'm not aware that power cycling actually damages the backlight itself any...
  • There is a laptop with three buttons!

    Sony Vaio C1 Picturebook series have three buttons.

  • Yea, I got an A21p for work, and it might be spendy, but it's a rock-solid machine. The third mouse button is a must, and it's there :-)

    - Mike

  • My laptop has a three button mouse... Sony Picturebook.
  • hmmm.... a few months ago....

    the college i attend has a laptop program, which requires incomming freshmen to pay out the nose for a 2 year lease on a laptop, then another 2 year lease on a newer laptop, which if you graduate you get to keep.

    sounds good right, well the major problem is we get compaq laptops because one of their vice presidents is a alumnus (i think gender is correct there, in any case, the vp is a member of the alumni :). not because of quality or price considerations.

    i haven't worked with too many laptops before, but i did not envision them requiring duct tape all over to stay in one piece (compaq armada e500), and yes peoples backlights do go out, the system isn't totally unusable, its just dark :)
  • This is similar to the LCD question, but it pertains to hard drives. I have been looking into drive lifetimes... and on a Tivo mailing list someone mentioned leaving the drive on (and spinning) all the time is the best. The idea being that the spin up of the platters is the most stressful part of the drives life. Is this at all true?

    Later.
  • Hard Disk's tend to fail after lots of use as well (or just get filled) I had problems with my old laptops hard disk and memory issues. The screen (not even an active matrix display) still works, but its not as nice as the thinkpad I use most of the time.

    I have also run into resolution issues (under x windows) as the display can only run 800x600 (old fujitsu lifebook 420) So the display's clarity really isn't the issue so much as the supporting hardware is!

  • [martha_mode_on]

    A laptop with a dead LCD need not be trash. It can be permanently installed in one of your company's conference rooms to run the projector for slide shows. Small and out of the way when not needed and that's ideal since most conference rooms are lacking for storage space.

  • Just get a new one...

    Would you still be using your 15-pound 486/33 notebook that you bought 5 years ago today?

    Notebooks get cheaper and cheaper as part prices fall through the floor. Just replace the damn thing!
  • My LCD screens (2 Notebooks - IBM Thinkpad thats 4 years old and a Compaq thats under 1 year) only fail when I drop them on the hard, hard concrete. :)
  • The laptop i use is a couple years old (cel300 i think) and if the screen has been off for a few minutes it takes several minutes for the backlight to come back up to normal brightness. its fairly dim right after the screen comes on.
    By the time a current laptop would suffer such a fate they'll probably have OLED's and such. Hopefully current lcd/backlights are improved over the older ones.
  • If this is a real concern to you, you might want to look into a few other options.

    One, is that many LCD brands, if they use flourescent Backlighting (like most Laptops do), often times the flourescent tube can be replaced -- sometimes with ease, sometime with difficulty. Examples of ease are the Mac PowerBook 1xx series, where a new tube is only a few bucks and can be replace in a a a few minutes. Examples of difficultly are my Fujitsu Lifebook, where the entire LCD panel itself had to be taken apart.

    The other option you have is, depending on how old you machine is and how much time and money you want to put into it, is to just replace the screen when it becomes a problem. If it's an 'older' (i.e. 1 year old) machine, you can pick up a new-from-factory LCD for 300 USD, or your can watch eBay for a model like yours with a dead logic board or something.

    Anyway, if it's your main machine, then I have a feeling that other parts of the box will go before the backlight does -- especially the battery and the hinge.
  • Judging by your nickname, polymath69, you are probably mathematical in nature.
    polymath
    a. n. A person of much or varied learning; one acquainted with various subjects of study.
    b. adj. Very learned.
    (OED)
  • IBM THinkpad 600X, three mouse buttons, works great with SuSE 7.0, sound supported via ALSA or kernel 2.2.18's OSS/Lite. Lucent driver from http://walbran.org/sean/linux/stodolsk/ [walbran.org] works with 2.2.x and 2.4.x kernels as long as you read the 1ST.README file and follow the directions. Main problem with the 600X is that the total RAM is not recognized on boot and it's not quite the N meg you think you have, but (N-0.5) M because of the "EZ-BIOS" or whatever.
  • Well, really, I did try and simplify the solution, since, as posed, the solution would be underdetermined. I need more data to determine the optimal solution: the cost of the system, with a depreciation schedule, the specific MTTF and MTBF of the system, backlight replacement costs, and time, with projections into the future, including contingency plans if any of the constituent parts reaches end-of-life in the service interval. Also, I think you would have to factor in the cost of the downtime of the system with a respect to lost productivity. You could recoup some of the cost by dedicating the laptop with a dead backlight to a home server, or possibly as a tax deduction, but that is a question better posed to your accountant.

    I think that this quickly changes from a failure analysis problem to an accounting problem, which takes it far out of my range of experience, which is primarily engineering.

    With one or two of the lifetime lengthening measures, and without expending the effort on the PDE solution to the problem, you can probably easily extend the lifetime way past the expected lifetime of the laptop, or at least past the "crap, I spilled Coke all over my keyboard" event.
  • I think your laptop's MB or something else will fail long before your LCD. The thing you would probably have to worry about the most is physical damage. I, personally have never seen a LCD fail, but that doesn't mean they don't. If your that worried about it, either get a LCD flat panel to plug into when your at home, or a 15 in monitor to plug into. For that matter, you can extend the keyboard and mousing device (trackpoint, touchpad or whatever) by throwing in a cheapy mouse too. Oh, and Cmdrtaco will wonder this too, but how come there are NO laptops with three mouse buttons???? Anyone who spends a lot of time under Linux or UNIX (FreeBSD or anything running X windows) will come to appreciate the extra button (no Apple, it's not that hard to figure out a lousy three buttons).
  • Well there's two! :) My point is it's pretty hard to find such notebooks (I bet i can't find one with three as fast as I can find one with only two mouse buttons! :)). My thing is there just isn't that many notebooks that work with Linux (100% ......not having the internal modem and/or ethernet work is not 100 %). I can buy/build a desktop with 100 % Linux support for just about everything. Can't do that with a laptop (easily anyway). Let alone try to find ones that come preinstalled (I don't need a preinstall, but some people do).
  • Actually I have heard good things about the Thinkpads. IBM is probably Linux's best supporter right now. Oh, BTW, can you use the ltmodem driver with 2.4?? Last I checked it was tied to the kernel that came with Red Hat 6.2. It was possible to load it on other's, but whether it worked or not depended on how different it was from the Red Hat one.

    Ok I just checked it and I see it has been updated....finally! Looks like some resourceful hackers hacked on the original to make it work similarly to the way the aureal hackers did. Actually a coworker of mine has this same laptop (I think) and he's running lilo dual boot with slack ware on the other partition. He needs to get a new HD cuz he has barely 1.2 gig of space and that's not hardly enough to seriously play.

    You are definitely right about the hardware though. I see most laptops getting replaced before the LCD burns out.

  • Here's an alternative solution to what you suggest Matt:

    Judging by your nickname, polymath69, you are probably mathematical in nature. The problems that you describe, brightness dimming over time Vs. power cycling breaks up very nicely into a linear separable partial differential equation. I know this because I've solved a similar problem for a harddrive (spin up/down Vs. spinning time). I'm fairly certain that the solution to the PDE is analytic and you will be able to find an exact solution, yielding an optimum amount of time to leave it on as opposed to turning it off. If it doesn't have an analytic solution, then you can use the linear simplex algorithm or find a solution using Galerkin's method. Each of these numerical techniques are fun and will converge to an optimal solution relatively quickly.

    For further info, I recommend MacCluer's industrial mathematics book.

  • I've been using laptops and other portable computing devices for years.

    Generally there are a few ways that an LCD will die. None of them have anything to do with the backlight. The backlights on my LCD displays have never failed. My earliest palmtop's case broke so it wouldn't stay open. Not an LCD failure. My next palmtop got smooshed and cracked the screen. My latest palmtop has a nick-mark on the screen because I accidentally dropped something on it. My first laptop had a depression in the screen becaue some @$^$ kicked it, but it was still usable. It finally died when the motherboard stopped working. Also not a LCD failure.

    Don't worry about your backlight. Wory about everything else breaking.

  • Make a reasonable compromise (Score:4)

    by Matt_Bennett ( 79107 ) on Wednesday April 04, 2001 @04:53AM (#316040) Homepage Journal
    You have another concern, as detailed in this PDF [landmarktek.com]. Backlight lifetime is going to go down as you increase the brightness. From a brief google search, backlight lifetimes run from 20,000 to 50,000 hours, with intensity decreasing with time, and end-of-life determined as 50% brightness of new. You may declare it too dim far before that time, but even then 20,000 hours is 2500 8 hour days, or almost seven years at 8 hours a day.

    That gives you some options:

    1. Don't run the backlight at 100% intensity- try to reduce the lighting in the areas where you are using the laptop. This saves batteries too.

    2. Turn off the backlight after something like .5 to 1 hour of non-use of the system.

    3. If you must leave the monitor on to be able to check things at a glance, reduce the intensity as much as possible.

    Also, just for the general lifetime of your laptop, use the power-down/suspend power saving features- laptops are dense little packages of electronics- which generate a lot of heat, but don't dissipate it well. Heat kills electronics and batteries, try to keep the heat down, and you will greatly improve the lifetime of the whole laptop, not just the screen. If you're not using it, and the laptop is warm, you're wasting power and laptop lifetime.

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