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DIY LCD Backlight Repair
Bill Nye (not the science guy) writes to tell us that InventGeek has an interesting article on do it yourself LCD backlight repair. From the overview: "Those of us that have used LCD monitors for a while know that over time the backlight starts to dim and will eventually completely fail. Leaving you with some electronic scrap that you could sell on eBay for 35 bucks or so. Well for less than $20.00 and about a half hour of your time you can replace the backlight and rejuvenate that monitor to as good as new condition."
Just FYI Fry's carries everything you need, from those special power modulators to mini flourescent tubes to repair your LCD's.
I have an old HP craptop, about three years old now. I was able to get a new inverter for the screen backlight for about 40 bucks from them... took off the front panel, put in the inverter (simple plugs), and it all worked fine. Ask your laptop maker if they can sell you the part without the service. It is an easy DIY fix.
Whoever stated that signature sizes should be limited to one hundred and twenty characters can just go ahead and kiss my
Here's a little more info that laptop users might find useful and I stress "might". http://iantha.vectorstar.net/ccfl.html#replace
gasmonso http://religiousfreaks.com/Actually there aren't any large capacitors in the backlight of TFTs. I've worked with some invertors and they don't peak at more than 1000V and normally operate at 600V.
The key trick with this jazz is to find the part number and buy a new one. Much quicker.
ah yes.. i did one of these for a friend of mine.. actually.. i offered to do one of these for a friend of mine with absolutely NO prior experience or instruction manuals...
heres how it went..
day 1. order replacement CCFL from ebay. luckily one seller had it in the original housing meant for my laptop screen. for 50$ + next day shipping - 65$.
day 3. put in new CCFL after an HOUR of painfully slow and arduous task. removing all the foil tape in once piece. saving and identifying the millions of screws. reapplying all the foil tape... fun. power up - no light. oh my. now whats the problem.
day 4. i realized there was an isolated power inverter circut board running power directly to the CCFL. my only guess was that this is bad and needed to be replaced. went online and ordered one from singapore. searched about 50 websites with nothing to go on but a circuit board p/n and serial number. found it... for 60$ + priority international shipping - 85$
day 8. installed new power inverter.. BAM works like a charm. reassembled entire laptop and gave it back to the friend.. since i quoted her at 100$ (another shop quoted her at 400$ and said they couldnt gaurante that it would work after)... i basically lost about 50$ on the deal.. but shes a good friend and i decided not to tell her how much it actually cost me in parts... after all, i told her it was about 50$ in parts and about 50 for a hours labor...
my advise.. do all your research before you get started. examine the inside of your monitor... see what work needs to be done.. look up the boards on ebay and elsewhere to get a feel for the price of your replacement parts... and if all else fails.. send it to me. ill do it for less than 400$...
Under normal condidtions Mercury is a liquid. Still toxic, but not breatable. If the tube breaks open it will be exposed to regular atmospheric pressure and should return to liquid state.
Still, if you can get $35 for a piece of junk go for it.
"And we have seen and do testify that the Father sent the Son to be the Savior of the World"
1 John 4:14
http://cgi.ebay.com/Silicon-Graphics-1600SW-LCD-Fl at-Panel-HDTV-34-units_W0QQitemZ7569824865QQcatego ryZ21517QQssPageNameZWDVWQQrdZ1QQcmdZViewItem#ebay photohosting
I happen to own one of these myself, and not only are they easy to repair, but their resale value is still outstanding.
I'm not fat, just big boned...
Yes, I've been able to fix multiple different laptop screens this same way as well. IBM T21's T41's etc... Most laptop lcd are relativly easy to dismantale is you've got a sharp set of #000, #00, and #0 phillips screwdrivers. I found almost all my bulbs from http://lcdpart.com/. I found there prices to be really affordable as well, $10 for the 14"-14.5" bulb! You'd be surprised how easy this whole procedure is if you can solder a few wires. ;-)
and it is easy to do. I'd start with the inverter first and then if that doesn't do it, look at replacing the light. There was an ask slashdot about obtaining lcd parts a while back. You can read good info. in that thread.
I also wrote up a journal entry when I fixed my dad's laptop, but I can't find it. (Note to self, do better job with titles)
I was nervous the first time I replaced a laptop inverter - but it was cake. The best place I found to buy the hp inverter I needed was ebay.
It's hard to believe that's how Micronians are made. Why don't we see it right now by having you both kiss one another?
Lead is horribly toxic, especially when it's in the right state.
if the backlight isn't dead, it's likely the voltage inverter. That piece of equipment ranges from $20 to $100.
Be really careful when handling the LCD screen itself and the ribbons that go to the monitor. If you sever a ribbon, prepare to lose a good 2" of screen. And no that can't be repaired.
I know this the hard way.
I've replaced backlights in powerbooks, both with official Apple parts (it has been
some years since THAT was available) and with generic lamps from third-party
suppliers.
Firstly, remember the lighting uniformity is HARD TO ENSURE. For the thinnest
displays (like modern Powerbooks) it's unlikely you can even FIND a source for the
lamp (2mm tubes are common, the available units are usually 4mm or the wrong length
or both), and if you do find it, getting the foam/mylar/backplate sandwiched
after replacement is going to be a chore. Expect a splotchy result.
The most recent display I had any good luck with was one of the Powerbook 500 series
(about 1995 vintage). That required a little work with a Dremel tool to fit the
available lamp (which was about 5mm too long), and took a bit of care during
disassembly. The plastic display bezel got brittle with age by the time
the unit was both out of warranty and failing to light up.
The 'supported' solution is to ship the unit to the manufacturer for
rebuild. Presumably, they DO have the right parts and a lot of patience.
My advice: pay the $400 (or whatever).
There's a lot less toxin in the lamp than in your last filling. More worrisome is the
wiring to the tube, which wants about 2000V to start. The wires are funny, rubbery
things, possibly a hightech silicone.
One very useful tool was a spare power supply; if your backlight was on a connector,
you can test it on known-good power that way, and an inverter replacement is a LOT
easier than lamp rebuild.
Ok, some comments from somebody who works with cold-cathode lamps.
First the mercury is pretty much a non-issue, it only escapes if you break the lamp and the ammount is miniscule anyway. As long as you are in a well ventilated area don't worry at all.
Second the manufacturer fits high-performance cold cathode lamps, subsituting hobby grade lamps is going to give you terrible colour rendering (I've seen cheap lamps that were more pink than white), and also the light output will be _considerably_ lower.
And last if you use the original inverter you are going to be overdriving the new lamp horribly. So the colour will suffer and the life will be affected (plus the lamps will run very hot indeed).
These are not at all like incandesent lamps, the inverters are tuned to the lamp parameters and cheaper/different lamps are likely to not match the inverter very well at all.
Or a ramp of cheaper white LED:s may also do the trick.
If builders built buildings the way programmers wrote programs, then the first woodpecker would destroy civilization.
Did this with a first generation iBook (Clamshell) ;)
If you google around you generally find alternative replacement lights for little money, compared to the 'official' stuff. Always worth to check for that.
Be sure to invest some time to try and find a servicemanual, that could save you a lot of headscratching. Laptops are a tad more complicated to dismantle AND put back together than bix boxes, everything is crammed in tiny spaces, lots and lots of screws, sometimes you have to go in in a particular step-by-step way not to break stuff etc... Inane stuff like, say, having to remove the optical drive to reach the connectors for the screen etc...
It takes time, but it's worth it, IMO. If you like that kind of stuff, heehee.
But if you don't you wouldn't be here, now do you?
Turn the LCD panel, plus an overhead projector, into a projection TV.
(I did it; it actually works quite well. I'm using it as my TV.)
Paleotechnologist and connoisseur of pretty shiny things.
If you RTFA you'll find http://www.lcdpart.com/doc/ccfl.html which lists many 2mm tubes.
The Christian Right is Neither (Christian nor right). See: Matthew 23, Matthew 25, Ezekiel 16:48-50
FYI on Mercury vapor. Generally the vapor comes from a tiny amount of mercury in the bulb that generates the vapor when heated. Florescent lights work in the same manner so if your scared of these tiny bulbs you should be in bind terror of the big tubes. Older bulbs you could actually see a big blob of mercury laying in the tube. The real danger comes if the contents are heated. That's why in the 1800s photographers got mercury poisoning because they heated mercury and waved the glass pane over it to develope the picture. Not real safe. I worked in a shop once that a carpenter built a curing oven and then installed florescent lights. I had to explain the problem and told him to replace them with incandescent bulbs. Mercury is safe enough so long as it's kept cool and you don't come in contact with it. That said I don't like working around the stuff and won't. If any gets spilled everytime the room gets hot you're breathing vapor. The only safe way of handling it is in a closed environment with proper scrubbers for the air.
You're exagerating. The worst thing that will happen to a child is getting a learning disability from that small amount of lead. Long term exposure to and/or larger amounts may kill them, but a two inch square piece of paint would not have that serious affect unless they are specificly alergic to lead.
I get a kick out of the seemingly sarcastic sounding "how do I fix this" things that I see here, and have seen in many other places. Fact is that with "tech" moving at such a pace these days, people (those with lots of ready-cash) are more likely to just dump this stuff into the trash (and landfills) and just go buy something new, rather than fix it.
I have been doing this sort of thing now since something like 1998 with relative ease. The only hassle has been scrounging up the cold cathode tubes that are large enough to cover the screens like the originals. Some will note that these have been conspicuously absent from the after-market parts shelves up until a couple years ago when it became fashionable to "light up" your box with colored lights. You quite literally had to know how to find them prior to this because they did not want them to be found. Any technician worth his salt knew that if you could replace the tube (and it wasn't hard at all to do), you could revive a computer or screen and make some money rather than having the user tossing this item into the landfills and spending whopping amounts of cash on "new models". (Yea, thats an accusation about the major OEM players; NEC, Toshiba and Sanyo; IMO)
As for the brightness issue... If you've replaced the tube and it's still dim, it's nothing more than the capacitors failing on your DC to AC converter boards. The caps are rated so close to tolarance in manufacture that with heat buildup and time, they fail prematurely. I've successfully pulled the boards and replaced the caps to bring them back to life assuming the transistors and IC have not failed. The brightness issue is nothing more than deviating the PWM (pulse width modulation) of the AC out to the tube. This change in PWM changes the resonance for the tube's circuit and hence it's brightness level is related to the PWM circuit efficiency. When the caps become leaky and dry, the circuit can no longer approach its normal or calculated PWM value or resonance, and hence your screen no longer can get as bright as it used to. Color temperature changed screens are the same issue. The cc tube is just more sensative to the current PWM and is lighting up in a particular color temperature; usually a brown or reddish hue.
Theoretically these LCD screens can last for many, many years if you want to simply replace these tubes and fix their circuits when they fail. Based on past history and my direct attempts to get these cc tubes and parts from several OEM's directly; replacing the entire LCD screen as a complete part; at a hefty price I might add; is generally your ONLY choice. More often than not, the replacement LCD panel cost more than the whole monitor did new!!!
I expect however that replacing the cc tubes as a standard repair will not be available because the folks manufacturing the LCD screens seem to control the access and if there is limited or no access to the parts, you only have access to "NEW" screens... or obviously new monitors!
Your market... you decide!!
Cheers;
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You may want to read about researcher Karen Wetterhahn, who died after spilling a drop or so of dimethylmercury, on top of the latex gloves she was wearing. Her story gives me the willies.
Elemental mercury is actualy pretty safe, organo-mercurial compounds are the toxic ones. Of course the popular press has made mercury an emotional issue like nuclear power.
Apocalypse Cancelled, Sorry, No Ticket Refunds
It isn't that dangerous. The tube contains a very small amount (2-10 mg) of mercury.
In another 10 years, I expect that they will call out the HAZMAT team for any reported spills of dihydrogen monoxide.
Actually, mercury thermometers are illegal to sell in my state. I remember a program to get people to turn in their mercury thermometers similar to police department programs to dispose of handguns.
Minnesota Session Laws - 2001
Legislative history and Authors
CHAPTER 47-H.F.No. 274
An act relating to the environment; restricting the sale of mercury thermometers; amending Minnesota Statutes 2000, section 116.92, subdivision 6. BE IT ENACTED BY THE LEGISLATURE OF THE STATE OF MINNESOTA:
Section 1. Minnesota Statutes 2000, section 116.92,
subdivision 6, is amended to read:
Subd. 6. [MERCURY THERMOMETERS PROHIBITED.] (a) A wholesaler, or retailer may not sell or distribute at no cost a thermometer containing mercury that was manufactured after June 1, 2001.
(b) Paragraph (a) does not apply to:
(1) an electronic thermometer with a battery containing mercury if the battery is in compliance with section 325E.125;
(2) a mercury thermometer used for food research and development or food processing, including meat, dairy products, and pet food processing;
(3) a mercury thermometer that is a component of an animal agriculture climate control system or industrial measurement system until such time as the system is replaced or a nonmercury component for the system is available; or
(4) a mercury thermometer used for calibration of other thermometers, apparatus, or equipment, unless a nonmercury calibration standard is approved for the application by the National Institute of Standards and Technology.
Sec. 2. [EFFECTIVE DATE.]
Section 1 is effective January 1, 2002.
Presented to the governor April 23, 2001
Signed by the governor April 26, 2001, 10:21 a.m.
I don't know that the dihydrogen monoxide has harmed our fish, but the mercury in our fish is enough to harm us.
Heh.
Mercury medical thermometers contain ~50X as much mercury as typical mercury/fluourescent lamps and a toxicologically significant dose is over 50X more than a thermometer. One would have to sniff hundreds of freshly broken lamps to get mercury poisoning symptoms from that alone. People should not lose sleep about the compact-fluourescent or similar tubes in their home/apartment/workplace/etc. unless thousands of them routinely shatter at once whenever ventilation breaks down.
Cthulhu Saves.
Yes, Dimethylmercury has as much to do with mercury as alumina to aluminium, cyanates to cyanide, hydrogen to water, etc. It annoys me when people can't even get the most basic grasp of chemistry.
I am one of many. My idea is not unique, nor do I expect my voice alone to sway you. I speak in a chorus of opinion.
I work in the fluorescent tube recycling industry. The hazard from the tiny 2mm-4mm back light is negligible. I've done tests with a Jerome type meter, and they read way below (almost non-existent readings) OSHA limits for airborne exposure. OSHA states that you need a respirator for a time weighted average exposure above .1mg Hg/cubic meter. You need to break a lot of tubes to get close to this, probably hundreds of the tiny back light kind. Mercury does vaporize at room temperatures! It doesn't need to be heated!
The type of mercury used in fluorescents is the inorganic kind, which is a hell of a lot less dangerous than organic mercury. Inorganic mercury will be filtered out of your blood and come out in your urine, just like most toxins, but organic mercury is small enough to find it's way into your body fats and stay there for good. Organic mercury is usually what you find in fish.
Mercury Vapor
NIOSH/OSHA Mercury Vapor Health Guideline
Cthulhu Saves.
Top tip: capacitance is measured in farads, not volts; a borg really ought to know that.
It's official. Most of you are morons.
It's pretty fun to do. A friend didn't want to fix his laptop himself but did want to save some money, so a few of us got togther and replaced his LCD backlight for him. It's really cool to see how many layers of various films are stacked up in there, as at least on this one we had to prety much completely disassemble the panel to get to the light tube.
:)
My friend got slightly the wrong tube length, so the two ends are a bit dark. There's a coupel fingerprints inside the LCD now, and someone's eyelash. If you end up seriously tearing the thing apart liek we did, get some latex gloves or somethign to help with the fingerprints, and try not to shed during the operation.
Yes it is an element and yes I was talking about compounds. Organic mercury contains covalent bonds between carbon and mercury. Inorganic mercury is when mercury bonds with anything but carbon, which includes oxygen, chlorine, sulfer, etc. Elemental mercury is also considered inorganic. I glossed over out of my own familiarity with the subject.
Cthulhu Saves.
I seem to recall that mercury has a fairly low vapor pressure... it's doesn't want to evaporate at room temperatures. It's happy just being a shiny liquid blob.
They did use to sell LCD panels that were designed to be used on overhead projectors.
Problem is that they sucked. You couldn't get an OH projector bright enough. Even an el-cheapo $1K standard projector blows the crap out of those things.