I've heard of people using florescent lights as their light source. Some use the long tubular design, some use the compact spiral design. Well I see one thing one could do to boost the light output even further.

What if you were to build a wall of florescent tubes, about 24"x32" or so. The get an over sized fresnel (around the same size) and use that as a condenser lens. Then have the condensed light go into your first standard size fresnal thats sits infront of the LCD. So your basically taking 768cu/in of light and compressing it down to 108cu/in of LCD. Thats 7 times the light compared to just making the standard 12"x9" array of lights (for a 15" 4:3).

Now my numbers are more than likey off, and I maybe missing some design details, however you never know, it could work. So I was seeing if anyone used a larger light source then the screen size they are using.

I did use fluorescents (the spiral kind). There are a few major caveats:

1. The light is not even. Maybe using tubes might solve that if they could be close enough together. I used 5 bulbs in an "X" arrangement, one in the center, four in the corners. The only way I could get even lighting was by using a diffuser sheet (off a stripped LCD panel). Mirroring the sides and back of the light box did help a lot though. I did NOT use a fresnel behind the LCD.
2. These bulbs don't seem to like heat all that much, which meant quite some cooling was needed.
3. Due to massive loss at the diffuser sheet, the projector wasn't terribly bright.

I'd imagine tubes might be more efficient, but haven't tried it. Depending on how close you can get them they might work well enough, but I'm fairly sure you WILL need a diffuser to even out the light. Using a fresnel to collect the light sounds like a cool idea, although I'm not sure I want an even bigger box

I'd have to disagree, I've found they are quite tolerable to heat, I have one fan with five bulbs and stays pretty cool and stable.

As for MyYz400, that would need alot of cooling.

What kind of bulbs did you use? The spiral kind? Or long tubes? I used the spiral bulbs.

I found a post by Nitrogen_Widget that said he was gonna try using 2 65 watt compact fluorescent flood lights. There were some on eBay a little while ago, but didn't see any today. I think Home Depot sells them too.

I used 4 100W Daylight Spiral Bulbs
and 1 75W (I think) Bright White Spiral Bulb

I've watched many movies on it and it never got too hot, a little warm maybe, but not hot. And none of them ever broke.

I guess its time to revisit that idea then New parts for another (experimental) projector are on the way already, so I'll have something to experiment with.

I'm starting a new project, using 2 of the mogul base 150w CFL full-spectrum grow lamps. My goal is to break the tubes apart (each "bulb" is actually 8 u shaped tubes) and create an "even" light source behind a 19" 16x10 panel. Looking into the future, a possible improvement is to use one of the microprismatic films to collimate the light behind the LCD.

Projection optics will be freznel, so no triplet in the traditional sense... the design similar to those 'make your tv 150" for 20$' plans. POV-Ray says it just might work...

Worst case scenario is that the project will result in one really bright LCD monitor.