Build Your Own LCD Video Projector

A while back I got frustrated with the fact the LCD Projectors cost so much money to buy, and figured that it couldn't be so hard to build my own. So I took a 2 inch JVC active matrix LCD (no longer on the market, but the LCD's on the right work pretty well) which was the exact size of a slide, took it apart, and mounted it inside my slide projector. This sort of worked. The downside was that the heat from the bulb was too much for the LCD, and the image degraded into swirls of colour after 15 seconds or so. Later on I worked out a beam splitter-type arrangement, where the light from the slide projector was reflected at a right angle to the LCD, and a huge blower fan was cooling the works, and it turned out pretty well. The picture was kinda pixilated, but I didn't have all the perfect lenses. But not bad considering I only invested $150 USD in the whole project. I don't have pictures from those experiments, but I've gathered together a lot of different related resources, and made up this page, in hopes that you'll get some ideas and figure something out on your own.   ( I'm going to put together another projector with the LCD on the right and take pictures of the whole process, and post the new article in the near future...)      Shop with our affiliates:



 
Projector spares and accessories, including projector lamps from Projector Point UK.

 

Highlights of people Building their own LCD Video Projectors

This person's project has progressed quite well, and has a lot of great hi-rez photos of their construction process on their site.

Kevin Wyatt build his video projector for under $200.  You can check out detailed pictures and a description of his project here:
http://www.geocities.com/zark5150/projector.html 

Other people building their own LCD Projectors:

-SJohn34126@aol.com - -Matthias van Ardenne - -srussell@naro.ca.anritsu.com (finished) 
-kma2000@megsinet.net
(finished)  - -KayeDoe@prodigy.net - -willem_za@hotmail.com


Bill Saunders
is one person who was building his own LCD projector.  I previously had his email address listed with the others at the bottom of this page, and he was getting a lot of similar questions, so he wrote in with the following notes on his particular solution.  This is one possibility, however there are many.

I cheated but here are the results I came up with:
Components:
1) - LCD panel projector  (ebay, $290 - Active Matrix a must!!! - 1024x768 Native (a lot scale up from 800x600) )
2) - overhead projector  (ebay, $40 - You want high lumens, long bulb life, cheap replacement bulbs, color balance wheel, (not absolutely required, only on high end overheads)
3) - TV card for PC  (I got a cheap on ATI TV wonder, $40 )
4) - Fast PC  ( I've got a 400mhz celeron but will be going up to at least a 1.2ghz AMD )
5) - Descaler  ( Free software from the net - requires a lot of CPU )
6) - Non existent "video level" plugin for descaler  ( see below for description )
7) - projection screen?  ( I do mine on my "textured" wall and it looks a little blurry. - (oh yeah, a dark room makes the difference, not dark just dim)

Ok here's the plan...
Buy the projector and LCD panel from ebay.  Do your research.  A lot of models on ebay are not that good.  I got a Proxima Ovation+ 920 for $290.  Its 1024x768 and active matrix.  It takes NTSC video in (probably PAL too but
cant be sure of that), S-Video in, and (S)VGA inputs.  I don't use the NTSC or S-Video but you could if you wanted.  Always lookup the manual online when you're evaluating a LCD panel.  Also sometimes pixels burn out.  They're not
really noticeable in tv/video unless you have a white image like snow.  Ask about the condition before hand.  Get a return policy if possible.  I actually got mine from a rental company called PC Rental.  Everyone wants to dump the panels and go with the integrated projector.  The Overhead projector should be good quality but that isn't required.  I got a Dukane SunSplash 2200? for $40.  Again do your research.  I looked up the bulb prices for this model on http://www.bulb-source.com.  My bulb type is $10.50 and last 75 hours (very approximate).  

Now bulb life varies greatly according to your electrical supply.   Poor line quality means poor bulb life.  Even if I only got 1/2 the life $10.50 / 37.5 = 0.27 cents per hour.  Good enough for me.  One feature my projector doesn't have that I wish it did: automatic bulb switching.  Some projectors have 2 bulbs and when one burns out you just turn a dial and the second bulb starts working.  That'll be handy when you're in a movie or game and the bulb goes out.  Anyway it all boils down to "do your research".  I got a cheap TV card for my PC.  I really want a HDTV card but I'm going to get the faster PC first.  All of the magic happens inside the computer.  The card I got cost $40 and works great.  Fast PC - to make your video look great it has to be scaled up from 320x240(or whatever NTSC is - its low) to 1024x768 and deinterlaced.  The
faster the PC is, the faster this can be done, and the more "action" that can be reasonably viewed.  Ie my 400mhz celeron does sitcoms and talk shows just great but watching fast sports gets jerky and gives me a headache.  descaler is the magical part.  These guys have produced software that replaces a really expensive video system.   Try http://deinterlace.sourceforge.net.  Oh did I mention fast PC above?  Anyway their system deinterlaces and scales video.  It looks great.

Biggest problem with the system above: white scenes get washed out to solid white and black scenes go to solid black.  There is a VirtualDub plugin as well as a gimp plugin that are called "level" or "Levels" that adjusts the image accordingly.  It dims the whites and brightens the darks.  The affect is to reduce the color space.  It appears to wash out the colors on a monitor but on the projector it lets you see the details in the dark areas and in the bright areas.  When a plugin gets written for descaler to do this real-time, this system will be great.  Not including the PC I got the whole system for less than $400.
Works great as a large computer screen (quake III when the monsters are 5 feet tall), and works well as a video projector (even without the level adjustment).

That's about it...Good luck.
Bill

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Here are some other LCD projector plans recently mailed to me by somebody, I scanned them in for you:

By the time you are done going through all this information, you should be able to build a video projector that will work as well as any one of the brand name LCD video projectors that cost hundreds to thousands of dollars, for less than $300.  To get started you need to know how these projectors work.  It's quite simple really; the projector uses a different light source other than the LCD monitor.  It magnifies the picture with one or more lenses and with the power of an alternate light source.  It then projects it onto a screen for viewing.

Why use an LCD projector over a standard CRT/TV frensnel lens magnified projector?  These types of projectors are large and heavy, and if you ever tried to make one, you will have found out that the picture quality is usually poor regardless of the type and size of lenses used.  Even if the room is pitch black!  The light source from a standard TV is just not strong enough to give you a clear, bright picture.  If you try and use a different light source, you'll find that the glass screen of the TV causes enough of a glare to overshadow the picture and you wind up not seeing anything.  You can get anti glare polarizing shields for a standard TV, but the cost is very high in comparison to an LCD.  LCD's, or Liquid Crystal Display TV's are perfect for these types of projectors because the anti-glare screen comes with the TV, and it can be adjusted for different light conditions.

Choosing an LCD monitor for your projector:  A decent LCD monitor which ranges in size from 2 to 5 inches diagonally, can be purchased via many internet or traditional vendors for under $100 USD.  For $20 more, it's possible to find one that will accept NTSC, PAL and SECAM, so it will be more useful to people in areas other than North America.  The LCD's will come with standard RCA video inputs, sometimes expanded from a 1/8th inch jack.  Pixel count, and therefore resolution and picture quality is quite important.  The better quality the LCD, the better the final projected image will be.  If you're choosing this method of building a projector, you don't have to worry about taking your LCD monitor apart, because this projector uses a direct reflection method, rather than a pass through transmissive method that would require you to take the backlight off your LCD monitor.

Here you will find plans, wiring diagrams, and a complete list of all parts & materials needed, with step by step instructions to guide you through the construction process.  After going through all of the information and plans, if you decide that you're not up to the challenge of building a projector similar to the one shown, there is information on where to buy a projector ready made, and explanations on how to set it up for use with your LCD monitor.














Where to buy pre-built projectors:
  You can buy these projectors pre-built.  Go to your favorite search engine and search for "autograph projector" or "drawing" , "tracer" or "opaque projector".  You'll find them on quite a few different websites, ranging in price from $30 to $400.  You can also try looking at your local hobby, craft or art supply store.

I did a quick search and came up with the following.  It's not exactly what you want for a video performance art environment, but it would suffice for at home in the basement TV and video watching:
Go to www.leevalley.com and look in the gifts section.  They sell low powered projectors, under which you can put an LCD monitor, and and use this configuration as a simple video projector.

Their 100-watt model costs $70 USD, and will magnify a 5 inch LCD monitor image to a 4 by 4 foot projected video image on your wall or screen.  You can see a picture of their projectors here.

If you decide to buy one, all you will have to do to make the system work with your LCD monitor is to build a simple box to raise the projector high enough to have the LCD directly under the viewing area of the projector.  Then hook up the LCD and do the adjustments as described in the setup section of the plans.

I haven't tried these plans yet, but it looks good, even if the diagrams are a little wonky.  My only suggestion to use something like this for shows, would be to use a stronger light source, better cooling as more heat will be generated, and maybe some heat absorbing material, with the lights placed either under the LCD, or somewhere where you can direct the light with mirrors so it shines through the LCD - but maybe I just didn't read this over carefully enough, maybe it's pretty good as is - who knows - get experimenting!  Now I'm feeling motivated to scan some more stuff in for the MadLab!

 

MISC Notes
DIY Projector Forum - awesome!
$6 Lens System - might be good?
Heat Dissipation Mirrors Source
High Lumen Light Sources
Projector Technologies Overview

a 3 LCD (RGB) projector diagram

I realize a lot of the above links have gone dead recently, mainly because the manufacturers of $5,000 video projectors don't want you to discover how easy it is to construct your own projector for 1/10th the cost!  Well anyway, with a bit of trial and error experimentation, you'll still be able to do it.  One trick is finding a good lense.  I was recently able to purchase two surplus video projector lenses on ebay for $10, and I'm sure you'll be able to find some lenses just as good with a little bit of hunting.  One person recently wrote in and mentioned this link.  - Good Luck! 8)  -David.