Things to do with an extra LCD ( slightly OT, but oh well )

**wylie-c** · 06-09-2004, 11:26 AM

So you have an extra LCD you're not using? Why not make your own home theatre projector!

The ingredients:
3M OHP Model 1730
Mobile Authority M71 7" widescreen TFT
- Non-VGA, 1440 (480) x 234 resolution
- composite input only
Blackout cloth screen ( with lots of wrinkles! )
100" projected image from a distance of 14 feet

The pics: ( some are quite large )

Testing the setup for the first time
King of the hill at 40" while testing
At 100" on the blackout cloth
King of the hill at 100"
Another at 100"
The stripped LCD
The OHP
One last pic, the wrinkly screen, but it shows the size of things and relative distance of OHP to screen

**Superduck** · 06-09-2004, 11:53 AM

That's very cool.

I've got a stupid question. Will that work with pretty much any LCD screen? And I guess any old OHP?

My coworker is looking to do the same thing.

Kris

**Ormo** · 06-09-2004, 11:57 AM

I take it the OHP is providing the light for the projection rather than the backlight?

very very cool!

**binary.h4x** · 06-09-2004, 01:14 PM

Originally Posted by Ormo

I take it the OHP is providing the light for the projection rather than the backlight?

very very cool!

looks like both

**wylie-c** · 06-10-2004, 02:36 AM

The backlight is completely disconnected, you can see it still attached to the board with the connector unplugged. The panel must be completely seperated from the board, except for the ribbon cable, in order for light to pass through it. Pretty much any old OHP will do the job, and with a vga or svga or higher lcd you can get a very crisp picture that rivals commercial projectors. Just not as bright. Unless you retrofit the OHP with a 400w metal halide, then it's very close.

**Pokey** · 06-10-2004, 03:01 AM

I have read an article about this, what is the distance of the OHP @ 100 dia" ?

Its cool, im thinking of doing the same thing, i have heard of doing it with a laptop LCD, what is the dia of the screen you are using?

**thelaw** · 06-10-2004, 11:01 AM

Its a good idea, for more details there is www.diyaudio.com projection section. There is commercial LCD's produced for this purpose. You shouldnt use a normal LCD that you love an cherish unless you provide adequate cooling. LCD's will fade at high temperature, and too much heat will turn them a deep black (although they usually recover). Either raise the LCD slightly and blow air underneath, or use a metal halide ohp (you still might need cooling even then). Halogen 400W OHP will make this job very tricky, as they give off unbelievable heat waste.

Use a massive fan like wylie's

**cadence117** · 06-10-2004, 11:37 AM

check out http://www.lumenlab.com/forums/index.php?act=idx

**brrman** · 06-10-2004, 11:47 AM

if its touchscreen, put it in your house and control your lights, AC, entertainment with it.

heh heh

**wylie-c** · 06-10-2004, 01:08 PM

Yes, there is a ton of good information at diyaudio. I have been reading the posts over there for quite some time. The pics were during testing, I do have it elevated off of the glass with a fan cooling the backside of the panel since then. If you have time to browse the diyaudio forum, it's well worth it. There are some peoples projects there that are simply amazing! To answer the question about distance, with a 7" lcd on my ohp, I have it 14' from the screen to produce 100 inches of movie watching goodness.