DIY High-Quality XGA Projector for ~$300

ranrub writes "Tom's Hardware Guide posted a guide to building your own XGA LCD projector from parts costing under $300. Major components are an overhead projector and a used 15" LCD screen. They even have a movie of the whole project on site! It's quite bigger and noisier than a standard projector, but most of our living rooms look like electronic junkyards anyway, don't they?"

Comments

Not quite the same...

[xchino]

The image is a bit blurry and usually darker than those expensive multimedia projectors. But the bulbs are cheaper to replace, and it's suitable for watching movies with your friends on walls and such. I'd recommend forgoing the overhead lamp and getting yourself a much more high powered light source, and a top quality fresnel lense, it will still probably be cheaper than the overhead projector, and having a brighter light source means a bigger or brighter picture. Couple one of these with a low powered am/fm transmitter and you're ready to host a Guerilla Drive in

Fun

[xpurple]

I did this years ago, and kept running into problems with cooling. Even with a fan in there the screen became washed out after a few hours of use.

Part of this might have been due to the fact that I was using a DSTN screen.

I have one...

[lxt]

Indeed, I have one lying around somewhere. It was a 640x480 LCD mounted in a metal casing about the size of an A4 sheet of paper, and around 3 inches thick. It would sit on top of the projector, but had a tendancy to overheat (the OHP light heating up everything inside the casing as well...).

Re:LED Bulbs?

[Misagon]

I just looked this up.

Luxeon Star/O produces 180 cd with color temperature 5500 K.
I don't know much about optics, but I found a formula: lumens = cd * 4pi.
So, 180 cd * 4pi ~= 2262 lumens.
So, with four of these would yield 9048 lumens where as a typical projector bulb would produce 10'000 lumens. I don't know if this is correct. Someone with more knowledge of optics should correct me!

The four LEDs would cost close to $100 + driver circuitry but they should last for at least five years.
A problem, as mentioned before is that common projectors are based on a single light source. We would need additional lenses or diffusers or we could get a splotchy picture.