Many years ago when projectors averaged about $2000 I decided to attempt to build my own for a fraction of the cost. Went to Home Depot and bought two security lights from lights of America and a lens from eBay.
http://www.audiovisualizers.com/madlab/lcd_proj.htmI tried to copy the projector on the left (link is dead now), got a blurry picture that kept bleeding with the heat. (Great job edwardvci !)
I then bought a CTX Ezrpro 550 on eBay for $250. Not a state of the art machine but decent for my budget. I chose this machine because it runs on overhead projector style bulbs that ran about $30, I bought a box of 12 on eBay for $20 (have gone through 3). Replacement bulbs for other better/brighter machines would run about $300-$400. I couldn’t afford a new machine, buying a used projector (brighter and better resolution than the one I got) and risking the bulb burning out wasn’t cost efficient.
Trying to make a projector imo isn’t worth it anymore. Projectors are so much better and less expensive than they used to be. I seen low end models for about $500 that are way better than anything that I can ever build. There are toy projectors like the ZoomBox (with build in DVD player) that run for $250. Replacement bulbs also dropped dramatically in price. I think you are better off buying a new projector even if its low end than trying to build one. Buy a used one on eBay if you can’t afford a new one (I did).
Going back to this post (the link), they used to sell computer projector panels designed to be put on an overhead projector. You don’t have to hack a LCD screen (yes, hacking is more fun sometimes) making one with a build in pc and TV tuner? Too heavy and bulky, I hang mine on the ceiling! I have a 25’ foot vga cord.
Relating it to this forum (BYOAC not BYO projector), two weeks ago I hooked up the laptop to the projector, played Capcom vs. Marvel with my buddy Rudy on the 6ft screen in the garage. We were pretty much evenly matched. The kids of the neighborhood think I’m the coolest guy that ever lived (I still didn’t let any of them play).