Follow Slashdot stories on Twitter

 



Forgot your password?
typodupeerror
×
Displays Hardware Hacking

A Practical Guide to DIY LCD Projectors 217

Compu486 writes "Inventgeek.com has a new article entitled "A practical guide to DIY Home Projection". The guide covers the basic theory behind projection and provides a step by step guide for a "Practical" DIY LCD Projector. Although this topic has been covered before, the perspective they offer is refreshing."
This discussion has been archived. No new comments can be posted.

A Practical Guide to DIY LCD Projectors

Comments Filter:
  • by Anonymous Coward on Wednesday July 13, 2005 @09:54AM (#13052902)
    In my day, we made our own movies using a light bulb and creative hand poses casting animal shaped shadows...
  • Finally (Score:3, Funny)

    by mfloy ( 899187 ) on Wednesday July 13, 2005 @09:55AM (#13052915) Homepage
    Now I can finally watch my reality TV shows on a bigger screen. This is truely a fantastic day.
  • I'd rather (Score:4, Informative)

    by Evangelion ( 2145 ) on Wednesday July 13, 2005 @09:57AM (#13052934) Homepage

    Go with LumenLab [lumenlab.com]'s plan, if I was to do this at all.

    And they have real pictures too, instead of faked images on thier site.
  • by Arthur B. ( 806360 ) on Wednesday July 13, 2005 @09:57AM (#13052936)
    I don't really get why one would want DIY here... Having a video-projector, say for home-cinema sake or gaming is mostly about quality of the picture. Apart from the sake of learning I'd rather buy one. Oh, and not a LCD one, at least a DSP. Although laser projection tech has been around for some time now, I'm really surprised that it's not used. Although sounds like a feasible DIY project.
    • I don't really get why one would want DIY here...

      Cost savings, and the fun of doing it, I guess.

      I've never seen one of these homebrew things in operation, but I share your doubts about the picture quality. Every overhead projector I've ever used has had pretty crappy geometry, and uneven illumination. They're also noisy and run pretty hot. (I know that's what the enclosure is for, but simultaneously getting rid of heat and noise is tricky).

      BTW, I think you mean DLP, no DSP.
    • I don't really get why one would want DIY here...

      No, what you don't understand is why someone would want an LCD projector. Whether it's homebrew or commercial, the picture quality will be basically the same. In fact, because of the larger form-factor of most home-brew projectors, you have the possibility of using a much, much higher-res LCD panel for your projector.
    • Although laser projection tech has been around for some time now, I'm really surprised that it's not used.

      Last time I looked into it green lasers were prohibitively expensive and blue lasers were completely untenably expensive.
    • I don't really get why one would want DIY here... Having a video-projector, say for home-cinema sake or gaming is mostly about quality of the picture.

      When I first went to university in the early-mid 1990s, they used the *same* method to project a computer display; a transparent LCD device (designed for the purpose) placed on an OHP.

      It was *horrible*. The OHPs gave (just about) passable performance under most conditions when used for their intended purpose. However, the optics were no better than they
    • I think the biggest thing with this isn't that you can make your own projector for a home theatre system (most people would probably be better off getting a designed system for that) but it does open up interesting other DIY projects.

      A few weeks back was the project where 2 projectors + cameras were turned into a realtime 2D fighter (it was called "kick ass kung fu" or something like that). Now if you have to pay $1500 per projector something like that is quite hard to afford, but if you "roll your own" it
    • Although laser projection tech has been around for some time now, I'm really surprised that it's not used.

      Laser projection is just getting started out at the very high end of the market (theater projection).

      Sony is currently demoing their Laser Theatre Dream Display at the World Expo in Aichi, Japan. What they are showing is actually three displays with a slight overlap (which actually works reasonably well except for blacks). Each display consists of many red diode lasers, blue diode lasers, and gr


    • In my research in low-medium end projectors (up to about $4000), LCD is better than DLP (which is what I assume you mean by "DSP.") Sharper, brighter, better colour, and no danger of the "rainbow effect" which plagues DLP projects and distracts or even give viewers headaches.

      DLP still wins in contrast, but you'll rarely notice the difference and newer LCDs are getting pretty good (2000:1 for the AE700U). The only drawback of LCD I've seen is the greater likelihood of dead pixels.
  • by LegendOfLink ( 574790 ) on Wednesday July 13, 2005 @09:57AM (#13052940) Homepage
    Nah, my idea is better. Re-wire a retina scanner to output a DVD stream, and then you've got the BIGGEST picture of them all.

    Although I did see Matrix 3 in the IMAX, and it was a little scary to see Morpheus's face. I mean, the dude had like 2-foot pores!
  • Hmm? (Score:5, Informative)

    by Sweetdelight ( 895373 ) on Wednesday July 13, 2005 @10:02AM (#13052993)
  • DIY day? (Score:3, Interesting)

    by Lxy ( 80823 ) on Wednesday July 13, 2005 @10:09AM (#13053064) Journal
    Is today's Slashdot being brought to us by the DIY network or something?

    Build a rack!
    Build a shelf!
    Build an LCD!

    I admire the geek who homebrews hardware, but this is getting rediculous.
    • Re:DIY day? (Score:3, Interesting)

      by nizcolas ( 597301 )
      Except in the article you don't build the lcd, and the housing is optional.

      However I must admit that I'm more inclined to do this than the version where you tear the lcd apart. I talked to our hardware guy at work and asked him if he'd feel comfortable disassembling and lcd for a project like this. His response was something like, "as long as it wasn't mine."
  • by Drog ( 114101 ) on Wednesday July 13, 2005 @10:14AM (#13053101) Homepage
    I've been reading up on this recently as I'm planning to build myself a home theatre in my basement this summer. Rather than buying or building a screen, I'm simply going to paint it onto my wall using a new type of paint called "Screen Goo" [goosystems.com] (I read a review of it here [asp.net]). Supposedly, it gives excellent results.

    As for the projector, I don't want to build this thing myself, I'm willing to spend the bucks. So I'll likely go for the Panasonic PT-AE700U, which I've seen reviewed here [projectorpeople.com].

    So that leaves me wondering what sort of PC or hi-def receiver to buy to power this thing, so that I can use cable, satellite, game console, DVD, PVR and the PC.

    Any advice would be most appreciated.

    • Off topic, and not quite what you asked for, but if you haven't settled on a remote control for your setup yet, I just picked up Logitech's Harmony 880 [logitech.com] and it is fantastic. I know I sound like a commercial (and no, I'm not affiliated with Logitech), but the Harmony is really the best thing I've found on the market for controlling a high-end system. There are LCD-only remotes that allow you to customize the button layout more than the Harmony, but I found that having to hunt for a button everytime I needed
    • by The-Bus ( 138060 ) on Wednesday July 13, 2005 @10:36AM (#13053306)
      Well, you will probably want to invest in a good DVD player. The decoding between players can have a big difference on image quality. I am not a videophile, but in my experience it's not so much the quality during slow, colorful scenes, but during very rapid sequences where you might see issues with playback. The Home Theater Forum [hometheaterforum.com] is always a great start (they have a very nice moderated DIY section), and I am looking into possibly getting an Oppo Digital DVD [hometheaterhifi.com] which has been extremely well rated. As a plus, places like HK Flix [hkflix.com] sell it with updated firmware (so you can switch regions easily on the fly), although I've seen it for $50 less on Froogle [google.com].

      As far as receivers, I can give you my analysis and feedback as a regular consumer (I wouldn't even call myself a "prosumer") of home theatre electronics. You definitely would do well in investing in a good receiver with as many inputs as possible, and don't get them from Circuit City / Best Buy / Fry's as they are usually $100 more than what you can find online. In reality, you will probably not need more than 3 or 4 component inputs (DVD + HDTV + Console + Other). Depending on the # of inputs on your TV/projector, this should put you in the $300-$500 range for receivers. Look for wattage ratings and buy from a well-known company (say, Harman-Kardon, Denon, Onkyo, Sony, Yamaha).

      Once everything is set up, get a calibration DVD like Digital Video Essentials [amazon.com] or Avia [amazon.com] to tweak your settings. It can make a noticeable difference.

      You don't need Monster Cables. If you have a friend at a store who can get you the discount (retailer markup is at least 100%), then they're fine. But you don't need to spend $300 on cables. Spend that money on better equipment.

      Just do your research. It's possible that over the next few months older models will be discontinued and be heavily discounted. That can always save you some cash.
      • Thanks for the excellent advice.
      • Good advice. Here's my further thoughts on it...

        Look for wattage ratings and buy from a well-known company

        Wattage can be misleading though, there are three different ways of listing the power, and each is 2x the previous one. Just make sure all five channels are the same wattage, and buy the same set of speakers for them all.

        Also, different amps sound different, and none of them are "correct". Maybe not so important for movies, but if you plan to use the same setup for music, you should try and a

    • You may want to read this for your screen first:

      http://www.hometheaterforum.com/htforum/showthread .php?s=&threadid=224307 [hometheaterforum.com]

      Less expensive than buying the screen paint, and from the sounds of it, both more effective and a nicer looking finished solution on your wall.
  • Call me when (Score:5, Insightful)

    by amcdiarmid ( 856796 ) <amcdiarm@@@gmail...com> on Wednesday July 13, 2005 @10:15AM (#13053110) Journal
    My wife will accept one in the living room.

    Otherwise this is just another "Overhead projectors with LCD panels make big ugly projectors that you cannot use anywhere but a darkened room" story.
  • Hmmmm (Score:5, Funny)

    by Phurd Phlegm ( 241627 ) on Wednesday July 13, 2005 @10:15AM (#13053111)
    I read one page--the one on "Theroy." I find it distracting when someone doesn't bother with even elementary proofreading. If the content is interesting enough, I can overlook it, but this didn't seem all that novel. Just so there'd be some discussion, I made a quick list of the first errors that sprang out at me in the "Theroy" page [inventgeek.com]. Doesn't everyone know some pedantic jerk that will edit their stuff for them?

    1. principals : principles
    2. cheep : cheap
    3. cellulous : celluloid?
    4. threw : through
    5. LCD's : LCDs
    6. Simi-gloss : semi-gloss
    7. portal : portable
    8. Walmount : wall-mount
    9. theroy : theory
    10. togeather : together
    11. its : it's
    12. . : ?

      I anxiously await the first person to point out a spelling or usage error in my post--it's traditional.

    • I anxiously await the first person to point out a spelling or usage error in my post--it's traditional.

      Dude! You misspelt "fuc... oh, forget it.

      ;-)

    • Well, I had a college professor tell me that the use of the dash should be carefully constrained, lest it lose its force through overuse. Twice in a short post would certainly be over her limits.

      Also, isn't a jerk a person? So should it be "a pedantic jerk who"?
    • I find it distracting when someone doesn't bother with even elementary proofreading.

      This would read better as:

      I find it distracting when someone doesn't even bother with elementary proofreading.

      Otherwise you may be referring to 'even elementary proofreading' which does not happen to be bothered with. It could also read:

      I find it distracting when someone doesn't bother with even the most elementary of proofreading.

      This gives that sort of sophisticated, British-accent sort of grammar that we all kn
    • Re:Hmmmm (Score:3, Funny)

      by sharkey ( 16670 )
      Simi-gloss : semi-gloss

      Actually, Simi-gloss is a brand name. Each can comes with its own painter-monkey.

  • a 1024x768 screen is going to look pretty damn pixelated blown up to 100" unless you sit quite a way back!
  • It's Not Worth It (Score:4, Insightful)

    by dafz1 ( 604262 ) on Wednesday July 13, 2005 @10:15AM (#13053116)
    The author of the article keeps saying it's better to DIY than spend $5K on a commercial model. However, you can get a decent projector for $800(or less if you buy a refurb non-current model). Plus, the picture quality is a lot better(supports 480i, 480p, 720p, and 1080i), and is in an appealing form factor.

    The other question is how noisy is the overhead projector? Remembering back to elementary school, those things were pretty loud.
    • Yeah, I agree. There's no way I'd want an ugly, noisy, low-res projector like that in my living room.
    • For $600 you can build a 1024x768 projector with DVI input and brightness equivalent to a 1500 lumen projector. The bulbs cost $40 to replace and last 18,000 hours. Parts are cheap and interchangable, should something go wrong (heat is the major issue.)

      Your $800 refurb projector will be an 800x600 with no DVI support and $300 bulb replacements twice a year. Good luck repairing it cheaply if something else breaks.
      • You're nuts right? Or you've never used an overhead projector. There's a reason they usually have a dedicated place for a replacement lamp - the lamps don't last long. I quote:

        In a test done by GTE/Sylvania on 10 ENX lamps, the range of life was 34.3 hours to 76 hours. The average lamp life for this batch was 68.7 hours, higher than the published average of 65 hours. However, the lamp that lasted only 34.3 hours is not considered to be defective.

        Okay, so those lamps will run you $6/ea in quantity. I'll
        • Oh, sorry I need to clarify. The $600 I'm talking about is not using an overhead projector with the standard bulb. It's using an all-custom enclosure and lens triplet with a metal-halide (parking lot) bulb, a-la LumenLab [lumenlab.com]. Noise is not an issue any more than it is with the compact consumer projectors as long as you use a 120mm fan. At that size, the fan can push a lot of air at a low RPM. The only real issues, in fact, are size and build time. On every other aspect I consider that it matches or beats other s
      • For $600 you can build a 1024x768 projector with DVI input and brightness equivalent to a 1500 lumen projector. The bulbs cost $40 to replace and last 18,000 hours. Parts are cheap and interchangable, should something go wrong (heat is the major issue.)

        Your $800 refurb projector will be an 800x600 with no DVI support and $300 bulb replacements twice a year. Good luck repairing it cheaply if something else breaks.

        Don't forget noise - much noisier, and a much larger form-factor with the overhead projec

    • Plus, the picture quality is a lot better(supports 480i, 480p, 720p, and 1080i), and is in an appealing form factor.

      Point me to an $800 projector that can handle 1080i (1920x1080).

      The other question is how noisy is the overhead projector?

      It's easy to replace the fan.
    • Seconded! (Score:3, Informative)

      by gilesjuk ( 604902 )
      Look at the cost of life of the bulbs in OHPs. Typically 50 hours and cost of about £30-50 here in the UK.

      Bulb life in a projector is typically 2000 hours (4000 in mine) and cost about £250 for the bulb.

      So using 2000 hours as an example:

      Projector cost £599 will last 2000 hours so total cost for first 200 hours is £599.

      Self made projector will cost about £200-300, for 2000 hours of use you'll need 40 bulbs at £30 a go which works out at £1200 for bulbs and
  • by Woogiemonger ( 628172 ) on Wednesday July 13, 2005 @10:17AM (#13053139)

    When commenting on lenses, it says:

    "Many lenses are coated to improve the optics of the lens. Products like Windex will severely damage these coatings resulting in pilling, fogging, or even etching of the actually glass. FYI, most CRT monitors are subject to the same conditions. Don't ever clean your CRT with Windex or similar products. Of course you would know this if you read the manual."

    Didn't know that! :) It's nice to get immediately useful info from an article about something you don't have time for.

  • I've been reading and re-reading the article to found out how the LCD acts as an imagery medium. How does this work? When I think LCD, there is the side that faces you and has pretty pictures and whatnot, and there is the side that has a plastic casing on it. How/where does the light pass through?
  • Now, I do admit that its bigger brothers in the 5K price region have a little bit better resolution, and a little better refresh rates. But when comparing the bottom line here 0.2K verses 5K... it still blows my mind. The real benefit here is in the budget for our version of the DIY projector, we got a really nice screen out of it.

    I bought mine on ebay for 600 dollars, and it has a remote control, will mount to the ceiling, and does NOT sound like a vacuum cleaner. Not to begruge anyone their project, bu
    • I bought mine on ebay for 600 dollars, and it has a remote control, will mount to the ceiling, and does NOT sound like a vacuum cleaner.

      The noise can be easily fixed by replacing the fan.

      The main issue that concerns me was addressed in the article. Commercial projectors tend to use very expensive bulbs, for no good reason. Your $600 projector may have a bulb that will need to be replaced several times a year, which costs $100+ each time...

      Point me to a $600 projector that uses a $10 bulb... Haven't

      • What I don't get is why they never use the equivalent of the bulbs used in car headlights. They're bright enough to light up the entire road, last forever, embarrassingly inexpensive, and I could go on like this forever.

        Build a proper enclosure based on a car headlight and reflective backing with some kind of focusing mechanism, and you'd get something smaller, quieter, using less voltage, and so on. I mean, sheesh.
        • What I don't get is why they never use the equivalent of the bulbs used in car headlights.

          A heavy-duty AC/DC adapter would be more expensive. When you're running on 120v AC, you really should use a 120v AC bulb for many reasons.

          However, there certainly ARE 120v projector bulbs that only cost $10 or so.

          In my experience, car headlights don't last all that long, and they don't come close to being as bright as most projector bulbs.
  • DIY? (Score:5, Insightful)

    by WhatAmIDoingHere ( 742870 ) * <sexwithanimals@gmail.com> on Wednesday July 13, 2005 @10:24AM (#13053194) Homepage
    How is this a "do it yourself" project? You bought an overhead projector. You bought the LCD display that was made to go on overhead projectors. You bought a screen.

    The only DIY here was "Make a box with a window in it" and that's not really a "Do it yourself LCD projector" now is it?
  • by Raunch ( 191457 ) <http://sicklayouts.com> on Wednesday July 13, 2005 @10:27AM (#13053227) Homepage
    I have to be honest, this screen is really worth it. It looks great in low light and no light situations and is very clear.

    Projectors look really good in low light and no light situations, on a sheet or a wall, or on your little brother. The test of a screen is how it does in situations with higher amounts of ambiant light.
  • We will be using some felt that we acquired at the local fabric store. Now I will say this on the note of the fabric store types: Not Geeks! These are the types of people that never get out and experience the world. And their idea of creative or innovative thinking is using a slightly-different-than-recommended shade of embroidery floss for their "There's No Place Like Home" wall hanging or pillow. So don't be surprised if you feel really uncomfortable in a fabric store. I sure as hell did! And people make

  • DIY? Where? (Score:4, Interesting)

    by The Fun Guy ( 21791 ) on Wednesday July 13, 2005 @11:09AM (#13053639) Homepage Journal
    All they did was take an LCD screen, designed to be used with overhead projectors, and put it onto an overhead projector. The only "DIY" was the case they built out of "partial board" and covered with black felt.

    My department bought one of those transparent LCD screens in 1997, back when overhead projectors were still to be found in every lecture hall, laptops were $3000 and LCD projectors were $5000 and as big as a suitcase. The idea was to use this to go from the computer screen to the wall screen on the cheap. It was used every once in awhile, but if you weren't using a laptop, it was a pain to use, since you had to wheel in a cart with a desktop PC.

    Once laptops got cheap enough so that they were commonplace, LCD projectors had gotten cheap enough that the department bought one and consigned the transparent LCD screen, with its terrible picture quality, to the back closet of the copier room. There, it collected dust, along with all of the other obsolete junk that no one wanted to use anymore, but had cost too much to just throw away.

    The transparent LCD screen was an ugly kludge, a bridge technology to mate the old with the new. Let it die.
  • Is that I remember in college a professor of mine using one of these overhead LCD projector doo-dads and she had to constantly turn the overhead off while lecturing because the heat of the projector would start to "burn" the LCD and the image would be distorted on the screen. After cooling down it would work again, but still during a 2+ hour movie or gaming session... I just can't see how this will work.

    Now overhead projector technology may have come a long way (hehe) since then but isn't this an issue? At
  • by larsoncc ( 461660 ) on Wednesday July 13, 2005 @11:21AM (#13053750) Homepage
    According to this link [cadigital.com] the Proxima Ovation 944+ is 8 grand new. Not that anyone would pay that, right? Well...

    None are listed on eBay.

    Finished auctions on eBay list at about 300. [ebay.com] That's fine, but try to find one!

    Kind of eliminates the ability to do this project, doesn't it?

    I don't understand why all of these DIY projects have to use some amount of unobtainium. Why not price out some NEW parts, ones that are currently on the market? Leave it as an exercise for the reader to find used or discounted products.

    Only then can you make a fair assessment of whether or not one of these projects is "do-able."

    I would love to see some names / brands of recommended overhead projection panels - but unfortunately, THAT is left up to the reader. I thought making these recommendations was a key part of a DIY article. After all, look at Woodworking magazine or any other DIY magazine - they all list the parts, the specs of the parts, and typically, a price or two with each.
    • I have to agree. I've read a bit about those as it seemed like you could save lots of money.

      But that was counting you could easily get all the parts for cheap (those 50% rebates on LCDs in big names stores I've never seen - or broken ones on ebay that sell for cheap - which never seems to happen either).

      Plus, most places selling plans for them also try to sell you some of the parts (lenses, reflectors, etc), and not for cheap either.

      When you add the REAL prices of all the parts, the plans, the wood (some
  • Comment removed based on user account deletion
  • I've built an LCD projector. Despite all the naysayers here, it gave an excellent picture, it looked pretty snazzy, my girlfriend thought it was cool, and it was much quieter than an X1, which is the projector I compared it to.

    I used a 17" 1280x768 flat panel monitor, a 250 watt metal halide bulb, a pair of 220mm focal length fresnels and a triplet lens out of a 3M 9200 projector.

    All you people bitching about how a DIY projector looks sitting in your living room should be ashamed of yourself. If you canno
  • by PhYrE2k2 ( 806396 ) on Wednesday July 13, 2005 @12:10PM (#13054270)
    Why oh why would anyone bother?

    I recently purchased a very lovely DLP projector for business purposes. NEC, 1024x768, 5lbs. Composite, RGB, Component, S-Video inputs, a remote, etc. all for about $1,000CDN ($815USD). Similarly, you can get units like this from major retailers for $750-$1500 with spare bulbs, cables, etc. This project has a cost of "$200-800", but realistically, you're in the higher range if you want a decent LCD panel with good resolution, inputs, etc. and a bright enough projector.

    So yes- this has the geek factor to it and all your friends will find it amusing that you were able to make a projector to fill your wall. These projects are intended to SAVE tons of money in DIY projects as well as add to the geek factor.

    Instead, we have a big clunking machine, built on parts with low bulb life, not intended to go for hours on end, poor cooling, and far from optimal quality (usually splotchy projection comes from the overhead projectors).

    Don't bother with this project. If you're going to spend this much, go out and buy a real projector. It'll be great for computers, home theatre, presentations, etc. and you'll be able to drag it over to a friend's house to have movies on a king sized bed sheet draped over his/her garage. :)

    The costs of real projectors have come down! FOur to five years ago, a good portable projector was $3000-$5000. Nowdays it's $750-$1500- cheaper than most backlit projection TVs. Go buy a real projector.

    -M
  • Just to dispel any rumors the The Man is making you pay $300 for a $40 lamp in a commercially available projector, the $300 lamp is a "UHE" type arc lamp and the $40 lamp is a halogen. The UHE is going to produce I'd guess about twice as much light, with 1/2 the power consumption, it's going to last about as long as the halogen (1500 to 2000 hr) and it's going to have a much higher color temperature.

    If you were really into DIY you'd homebrew an arc lamp power supply, but it's tricky, you can't just plug th
  • Building a LCD projector is a bit like building an old-style bicycle with the one huge wheel and no gear/chain system. There is better technology now, called DLP. There is no reason to mess with LCD anymore.
  • Like another poster mentioned, this article is so un-DYI it took my breath away. Buying a cheap projector, lcd intended for projector and turning the lights off is NOT DYI, it's a 20 years old idea. The LumenLab link above is tons more interesting, though it didn't answer the two main questions I've had for a loooong time as I also want something like this, mainly low cost/heat/power LEDs and the lens/mirror setup for more than just straight ahead projection.

    1. I don't want a small room that would love

  • Probably sometime this coming winter. I have browsed various forums and such extensively on information about how to do this, most notably the Lumenlab [lumenlab.com] site (btw - this is an excellent resource - some of the forums you need to be a customer to access, I like the site so much that when I do get around to building, I plan on getting the plans to get the better access).

    Currently, I have most of the parts I need - mainly, I just need the proper fresnels and wood to make the case. I have the LCD, the projection

It is easier to write an incorrect program than understand a correct one.

Working...