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Projector Torture Test: LCD versus DLP
An anonymous reader writes "A ten month torture test of five LCD and two DLP projectors shows LCD images deteriorate during extended use." Not surprisingly, if you run an LCD projector for 4000 hours, it deteriorates... of course, if you're staring at a projecter 8 hours a day, for 500 straight days, maybe you should go outside ;)
In other news...
most materials react in unplesant ways when exposed to 4000 hours of consistant bright light.
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From Ape to Man: Evolution
The LCD isn't deteriorating after 4000 hours, your eyes are.
TLoM: Nerds + DDR + Rednecks for the win!
I go outside plenty. Just because a projector is run 8 hours a day doesn't mean I don't. The pool hall I hang out at has gone through dozens of projectors in the couple years I've been going there. It doesn't take long before a new one starts looking like crap.
Does this happen with LCD monitors as well?
> if you run an LCD projector for 4000 hours, it deteriorates... of course, if you're staring at a projecter 8 hours a day, for 500 straight days, maybe you should go outside ;)
But there are plenty of applications for these things where the display is permenantly turned on - think of a store display - or an airport information system - or high end adverts. In those cases, running 24 hours a day is very likely - and having the damned thing fail after a mere 166 days would suck badly!
It would have been nice to see the lifetime of large plasma panels in the survey too.
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then again if you think about it, most educational places (schools, colleges, uni's) usually use projectors alot.. So.. figure that projector is in use for 8 hours a day for a year its going to die off pretty fast..
Then again, anything that displays gets a bit.. dirty after a few years of use..
I've left to find myself. If you happen to see me, please, keep me there until I return.
How did they fair in the "drag them behind the truck, and dip them in raw sewage" test?
My old goldstar has yet to be beaten, but the MAGs have generally held a strong 2nd place.
-If you would like to report a giant panda sighting, press 9, and give the name of the laundromat
Compared to war, all other forms of human endeavor shrink to insignificance. God, how I love it. - Gen. George Patton
If I leave one image sitting on my LCD projector too long, yes, it will burn in a bit. But the burn in goes away after other images are shown. Typical desktop use gets no burn-in, while long bouts of Shadowbane will leave little yellow pock-marks when the fixed menus are. This goes away after browsing the web a while.
The problem with DLP projectors like the one my roomate bought is the "screendoor" effect that makes it look like you are viewing the image through a screendoor: little black boxes around every single pixel. This is an effect that is there from day-one and never goes away!
Will my LCD eventually get permanent burn-in? Perhaps. Still it's better than the screendoor.
Ink jet printers have very different running costs due to different costs for replacement ink cartridges. Does anyone know of a breakdown of running costs for different projectors or at least can share some experiences?
we also have a DLP project or aswell.
the company, actually the whole industry would like to switch from film to digital projection to save cost.
Guess who is pretty much the only player in HIGH powere digital technology, you guessed it TI. TI makes the DLP projectors we all enjoyed watching StarWars/Disney animation on. Now you say that some project running for more than 5000 hrs is never going to happen at your housse, or maybe at your office but consider this.
our current project with bulbs, can go for about 8000-10,000 hours before the bulbs needs replacement. so we got through about 2/3 bulb a years per projector.
but only switch the bulb.
now the problem is that if after 8000 hours we have to switch more than just the bulb
(which is the case when a digital project goes bad if you ever owned one)
then this could really hurt TI in getting the theathres to switch over.
and the "bright light" is really the paramedic's flashlight as he checks your ocular dilation.
You can't judge a book by the way it wears its hair.
Annoying eh Jimbo ? whatever TI's motives, maybe you expected to grab marketshare with slightly crummy cheap projectors, not telling anyone about the flaws, then sell everybody new projectors after the old ones have become obviously tainted, pretending you didn't know about the defects in the first generation ?
It almost sounds like what a certain OS manufacturer has done years back.
"A door is what a dog is perpetually on the wrong side of" - Ogden Nash
Here's one. Hardly technical (the site is a high level type site) but very interesting.
8 hours a day for 500 days is about equal to 15 hours a day for 10 months (approximately 300 days).
Breakfast served all day!
If you stare at a CRT for that long, the radiation will most likely cause an inoperable brain tumor...
Only if it's a color CRT (which, even with modern designs, generates a non-trivial amount of soft X-rays due to the electrons slamming into the shadow-mask).
Black-and-white monitors make much less X-rays, due to the lower accelleration voltage, lower beam current (i.e. fewer electrons) and lighter target. Meanwhile, the charge on the screen tends to suck the dust out of the air in front of the user's face. There is still some X-ray from the screen. But some studies have estimated that the reduction in risk of lung cancer from radioactive and/or chemically-reactive particles of inhaled dust more than compensates for any increase in risk from the small amount of X-rays from a B&W CRT.
Of course who uses a monochrome monitor these days?
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
According the to article, "TI and Munsell ran the projectors continuously 24/7, replacing bulbs as needed. Each projector was stressed continuously for thousands of hours."
There really wasn't much information provided on the methodology in this article. Did they leave just the one image or did it shift thru? Were any of the projectors shut off at any point (besides changing bulbs)? What were the conditions of the room/area in which the projectors were stored - ventilation, sunlight, etc.?
How many purchasers of projectors are going to use them non-stop? Just imagine such a stress-test of your Intel or AMD processor - 8000 straight hours of 100% CPU activity. I'm sure that could burn out a processor that would survive 8000 hours of activity without a hitch. The longevity of the LCD monitors may be much better than this implies -- which could be better tested under "normal" conditions.
My last thought is that I don't completely trust a "scientific" test done by a company to show the advantages of their own system.
I was taking one day at a time, but then several days got together and ambushed me. (from a Rhymes with Orange comic)
I'm in college and I see projectors used in large lectures ALOT.
So these projectors are used all the time. 4-5 days a week for a school day.
Any ideas?
-Grump
Is it true that more people vote for the winner of American Idol, than vote for the president? -Ali G.
Does anyone have a page that lists the technical details of how DLP works? The picture of the slide wasn't very technically detailed. I'd like to see how these work.
There's a fair amount of info on DLP at dlp.com. They have a rather high level "Technical overview", but if you look in the right place, you can also find a small White Paper Library, which has a number of papers that are fairly technically detailed but (IMO) still quite understandable.
"OT: did any subscribers see the "Microsoft DVD standard" article that was posted in TMF? It caught my eye and I refreshed the main page and it was gone, replaced by this article. Do the editors revoke certain articles before they go live? Was there a major factual error or something? "
OMG! Are you saying they actually took down a dupe?!
"Derp de derp."
And, they are right.
The lamps degrade over time, as well as the panels.
I see so many projectors fail due to non-cleaning.
panel overheats are an issue... because no end user really owns a projector, they usually use one at work and none of these people bother to clean the units filter.
This just adds to the speed of the failure. most projectors I see have failures of the lamp and ballast units before the panels, probably because I get these downed projectors, find them filthy, clean and repair them before it kills the panels.
I have seen many, many kinds of projectors in both LCD and DLP, and the ones that seem to last longer are DLP units.
LCD units start biting the bullet after 3-4 years and usually after 2 years the image quality is starting to degrade.
My recommendation to anyone that has ant of these projectors is to clean them regularly, allow them to cool properly (another BIG problem) and, replace the lamp after the recommended usage.
some are 3,000 hours... some are 2,000...
If you do not replace the lamp after the usage limit, you risk an exploding lamp, damaged ballast, or main power supply. if its a DLP unit the color wheel can be shattered by an exploding lamp. I have had to replace quite a few of these because of this.
The projectors I find that fail the LEAST are made by Sharp and Toshiba. these are well made units that have lifespans of 10 years or more.
I see 10 year old sharps all the time. altho, the panels are about wasted.
Remember, keep the filters clean, allow the units to cool properly and change the lamps when recommended, and your unit should function for many years before needing service.
I hope that someone finds this infoarmation informative and useful.
"Has anyone here used any of these high res projectors to put movies and TV in their homes?"
:-)
I do this. I have a DLP projector which has a resolution of 852 x 480 in 16:9 mode (using TI's original dual-mode chip). This happens to match the native resolution of DVDs (which are 720 x 480 - remember that DV to PC conversion factor).
The recommended maximum screen size for the projector is 80" (diagonal). I therefore used a 100" screen.
This makes for an impressive image, with some caveats. The room must be movie-theater dark, and if you remember reading movie/DVD reviews where the reviewer complained about washed-out movies and you never saw a problem - you will know exactly what he was talking about.
The setup is coming up on its one-year anniversary. I'm still happy, my friends are still jealous, and the original bulb has a few more hours left on it.
A.
...bringing you cynical quips since 1998
I hate to moan[0], but this is _really_ not news!
My flatmate got a DLP projector on eBay.
Before he bought it he did a little research on it, and I did too. We both came to the same conclusion - DLP is better than LCD.
If you look this up on Google I expect you'll find what we did - every retailer I checked said DLP was better (and that what small shortcomings it does have in comparison to LCD are being rapildy overcome with some new 'magical' rev 2 chipset[1] which seems to eliminate them).
I think that even after 5 min research on the web (or by asking your retailer) you'd know the answer to this question - and that all retailers and projectionists seem to be largely in complete agreement - so I don't think this article is newsworthy.
[0] That's a lie - I like to moan.
[1] The name of it escapes me.
For some pretty honest feedback from projector owners and experts, check out avsforum. Check out comments from owners of dlp, crt, and lcd projectors. The folks in the forums are not afraid to either praise or pan a particular projector (or manufacturer or reseller), and they have been a great help to me in sorting out the various factors during my seemingly endless quest. (Actually, I'm just a bit too chicken to drop the $$$ right now.)
And there are quite a few factors worth noting. For instance, some people may be bothered by the "rainbow effect" that is generated by dlp projectors. Others may not be affected by that, but may be bothered by the "screendoor effect" of lcd projectors. Still others may be affected by the "pocketbook effect" of purchasing these things. I may well end up purchasing an LCD for around $2000, and then throwing it away after 4000 hours. (Which for me would be many years, since I watch less than 10hrs of TV per week.) Or I may spend around $4000 on a DLP and plan on keeping it a bit longer. In any case, I don't think I can make a bad choice since South Park will be kick-ass on 100" screen.
Something worth noting is that Sony does not produce any DLP projectors. They do produce CRTs and LCDs. While I'm not a huge fan of Sony, they do kinda have a decent reputation in the consumer electronics field. So to me, their presence in the LCD market lends a bit of credibility. (The HS-10 is getting killer reviews, and it's only around $2500.) Also worth mentioning is the fact that DLP projectors can suffer from image burn-in, while LCD projectors do not. It doesn't mean that LCD is better than DLP. But these are some of the differences worth knowing before dropping several thousand $$$ on a projector. Again, check out avsforum for lots of insight into the different technologies.
If you are interested in purchasing a projector, do your research. You'll probably find that there isn't any one "best technology" to go with.
The short answer is that there's a small panel (DMD, digital mirrored device) with one tiny mirror per pixel (aka, over a million). Each mirror is individually motorized and flutters back and forth. One position reflects the light from the bulb down through the optics and to the screen. In the other position, it reflects the light into what's basically a light absorber.
Total light output is modlated by how much time the mirror is in the on position. The can each litterally flutter on and off over a thousand times a second. On dark areas of dark scenes you can see little scintelations of when individual mirrors flutter to the on position for a fraction of a second.
The fancier projetors have a light beam that's broken into red blue and green which then bounces off of three DMD panels before being recombined. The cheapie (less than $15K) ones have just one light beam that passes through a color wheel.
The color wheels typically have either RGB, RGBW (white), or RGBRGB. Better projectors have the RGBRGB wheels and spin at a higher rate. The result is that the projector winds up displaying a red image, a blue image and a green image in sequence. On fast moving items certain people (like me) are suscepible to seeing the different colors individually unless they spring for a higher speed color wheel, a triple DMD projector, or some other technology like LCD.
One last tidbit on the color wheel is that there is a new scroll color wheel coming out where at any given time there is a red, blue and green section being displayed over one third of the screen. They look like a pinwheel or one of those swirly lollypops. The trick to them is that the colors are actually dichoric mirrors so that only one given color light passes through while the other colors are then reflected back and hopefully recycled through one of the other two colors. It should more than total brighness while also lessening the effect of a slower speed colorwheel. Should be interresting.
> of course, if you're staring at a projecter 8 hours a day, for 500 straight days, maybe you should go outside ;)
:)
Unless you're playing Halo on that projector, in case it's perfectly acceptable.
..Jeff Keegan
seven syllables explain TiVo: kee gan dot org slash ti vo
Dude, totally different. The chroma bug is an artifact of the fact that colors on a DVD are actually at a different resolution than luminence (black and white) data. Most new DVD players are chroma bug free. The Panasonics are the safest bet.
Splotches are actually particles of dust blocking some light on one of the color panels. Take the projector far out of focus and the dust particle will come into perfect view. Just attack it with a can of compressed air. Also, really old projectors are going to look like hell if for no other reason that the new ones look really good.
Well, except for CRT projectors. Those things are still cherished even if the unit is 10 years old.
Big displays run continuously in control rooms and advertising applications. There's thus a market for long-life displays. Unlike home and conference room environments, silence isn't as critical. So aftermarket cooling solutions might actually sell.
http://www.optomausa.com/DLP_demo/example_third_pa rty.htm
Basically a square of very tiny reflective mirrors with a spinning colour disc to colour the light they reflect.
DLP = Digital Light Processing.
One way to get a stereoscopic 3d image is to use two projectors, both aimed to the same place on a silver (polarization-preserving) screen. Each projector has a polarizing filter in front of the lens. You send the left image to one and the right image to the other. The viewer has to wear glasses that have perpendicular polarizing filters so each image gets to the correct eye.
If you want to experiment with using two projectors do this, you will have much better success with DLP.
I played around with it and found that the light coming out of my LCD projectors was somewhat polarized. I worked out a way to put the perpendicular filters in place on my LCD projectors, but the light level was cut significantly by the filter. Any decrease in intensity is supposed to be unnoticable using DLP.
Maybe it doesn't matter though... it was such a pain keeping the images from the two projectors properly registered that I gave up on it after some experiments. Also, there's not much in the way of software that works out for 3D this way. I tried it using the two projectors logically connected using Xinerama and a Java applet that let me choose to show 3d images side by side. It was fun but if the images don't register well you'll quickly get a headache.
I have a DLP projector - Infocus LP330 - that I use for movies. It only cost me $900 used, and I use it to project an image about 75" (or so) wide on my living room wall. Image quality is good, but not great, and there is a halo of light that surrounds the projected image. A cloth-bezeled screen setup would solve my problems; right now it's just on my wall.
... ahem ... friend) is over, nothing beats an entire living room wall worth of screen real estate. Toss in a decent surround sound system, and you've got yourself maybe $6 worth of the $10 a movie ticket costs. I haven't been to the theater in months.
Any consumer who uses a projector to watch TV is, in my opinion, not focusing their monetary efforts in the right place. A substantially-sized HDTV these days is less than the cost of a projector, and will undoubtedly look better in the middle of the day.
However, when it's dark out, your friends (or
Using the XGA input is also great for parties and mp3 visualizations, displaying music videos, whatever.
The dangers of knowledge trigger emotional distress in human beings.
In short, it is a very, very fast RGB strobe sequence that has no equivalent that I know of in any other display technology.
Some early color movies (filmed with the Kinemacolor system, before the Technicolor sandwich approach became feasible) had the same sort of strobe effect, except it was RG not RGB.
Will I retire or break 10K?
You aren't going to see theatres with a staff of geeks, modding projectors. If you think there is a market for reliable projectors, you need to manufacture the projectors, feature-complete, and provide massive warranties. Companies don't pay several times as much money for some feature, they pay the money for the assurances of the reputable brand-name that this will do exactly what it claims.
How many companies could easily use $200 walmart PCs, but instead, buy lower-end computers for $1000/piece from Dell/HP/IBM? They want the assurance from the company that they have been tested, and will work perfectly, as claimed.
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