DIY Video Projector Part II

[declined]

I don't know if this has already been covered but i have been searching for the last couple hours and didn't find anything so here I go:
I have bought a 5.6" TFT LCD screen that works okay BUT when I remove the backlight it is SO terribly dark! I don't use a high-power-lamp yet,but it's coming soon ... will a 400W metal halide bulb do the trick or are there LCD displays that aren't transparent enough to use for projection? Is this because of the polarisation I heard about?

Something completely different: Uvodee (at least I think it was him) said i could get those very thin flatcables from molex, but their website doesnt show any flat flex cables, only the connector.
How ands where can I order -the right- flat cables to remove my cd from the PCB?
Thanx a lot for any help...

[ywh]

Dell 15" LCD

[declined]

Sorry but I dont see the link to the LCD transparency problem?!

BTW: -very- nice projector setup! Wow such a sharp image

PS: where did you find those flatcable extensions? I need some of those but cant find them and also: if I would find some, how could i connect them?

[zardoz]

Originally posted by declined
I don't know if this has already been covered but i have been searching for the last couple hours and didn't find anything so here I go:
I have bought a 5.6" TFT LCD screen that works okay BUT when I remove the backlight it is SO terribly dark! I don't use a high-power-lamp yet,but it's coming soon ... will a 400W metal halide bulb do the trick or are there LCD displays that aren't transparent enough to use for projection? Is this because of the polarisation I heard about?

Something completely different: Uvodee (at least I think it was him) said i could get those very thin flatcables from molex, but their website doesnt show any flat flex cables, only the connector.
How ands where can I order -the right- flat cables to remove my cd from the PCB?
Thanx a lot for any help...

I have a trash sharp screen here and have noticed the same thing about the transparancy level (or rather the lack of apparent transparancy) I am waiting for my gear to arrive so dont have much comment about it in particular. But I can say I had a 400 watt MH HID next to my dud panel (last night... doing reflector tests) and quite a bit of light appeared to make it through. Keeping in mind that the LCD had no feed to it and I did not have any reasonable "light box" constructed. I for one hope that the polarization on my new panel is done in the same manner as this junk Sharp lcd. The dead pannel had from back to front as follows.....1 plastic/metal backing for back light
2 sheet of ULTRA WHITE relctive type material
3 a plastic sheet that accepts the light from the CCFL through and along it's length, then act's as a "light pipe" from what I can tell to "backlight" the entire surface of the screen
4 a two piece assembly of polarizing sheet
5 the LCD panel itself
6 some sort of material on the screen face...I believe this is an "anti reflective" treatment to make daytime viewing on a laptop more tollerable I am hoping that this coating doesnt pose to be a problem as I dont see a good way of removing it

What are you running for a lamp now?

zardoz

[MatrixQ]

Hello,

I've been lurking here for quite some time, reading your various threads. I must say, you all have inspired me to build a DIY projector (and let's face it, a 10,000hr+ bulb is VERY attractive).

RedDevil: What kind of LCD are you using? I don't think this was posted, but i've read ohh so many threads.

Thanks,
Desmond.

[declined]

What are you running for a lamp now?

try not to laugh... just a standard desktop lamp, pointed at my lenses and lcd... I guess that explains the little brightness... But I am looking for prices of 400W MH bulbs so that should be like -a zillion- times brighter!
I havent started building my pj yet: its just some parts standing on my table...

I was just worried about the lcd because the other lcd i checked was much more transparent than my new 5.6" tft lcd. It was the little 2,5" screen on my camcorder.

But if the lcd turns out to be OK, then the only big problem left is finding a flatflex cable to make an extension to put my lcd further away from the electronics board... NO idea where to order those cables/connectors. Anyone an idea or link where I can order from Europe? (Belgium)

[daveb]

You may or may not remember me, but I was an avid participant here in the April - June timeframe. I was working hard on my own DIY system. Then I shorted out the power supply that feeds my LCD. Little whit puff of smoke, and that's all she wrote.

So I give up. I'm selling the whole thing. First and foremost, a brand new (less than 1 hour use) 400 Watt MH bulb/ballast/coil/capaciter kit.

Plus lots more stuff. Lenses, mirrors, reflector, OHP parts. Please check out my e-bay sale, where I've just listed. I know there are lots of success stories on this forum, but I'm afraid I've tried and failed.

I wish the best of luck to he or she who succeeds with this equipment.

Thanks,
dave.

Please see my sale at http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=2080266568

[zardoz]

Declined: If you are looking for the standard "High Bay" type HID's (like in factories and warehouses) try your local building wrecker. I got 2 ballasts and one el crapo reflector plus 2 working bulbs for $50.00 cdn. The used bulbs will do fine for me till I get all the optics and such set-up then I'll go and buy a new bulb.

Got my card...now to wait for my panel...I hate waiting.

Tested my reflector last night (big shiny bowl) my prelim tests look like I should go ahead and punch a hole in the bottom and try the lamp with the arc tube 90 degree's to the bowl's opening.

I've been advised by a trusted friend that I shouldnt need a reflector with the HID, and I think he is right. But at the cost of a $20.00 stainless steel bowl I just cant resist. The lamp is "wicked bright" all on it's own, but with the reflector it does seem to "focus" the light much better. (besides the wife allready has a bowl for mixing her bread dough...she cant use 2 at once ~s~ )

zardoz

[cosmic023]

Hi All,

I've been reading both parts of the DIY projector forum for a few weeks now, and there is some interesting stuff.

I had delivery of my ASK impact24 LCD overhead panel last week, which i bought off e-bay, and the specs look good.

The downside is my OHP hasn't arrived yet, it should be here later today. (Nobo 90 OHP) Has anyone got any specs. on this overhead projector, as i cannot find any info ??

Check out this site that someone has put together, using this panel and with a spec list as well at the bottom of the page.



I'll let you know how i get on, when the OHP turns up !, I've also posted this in the good / bad panel guide as well.

Cheers

Cosmic023


ASK Impact24 LCD Panel

[declined]

Okay... I have a question that might seem totally stupid but I'm sure there is at least 1 other person that once didn't know this :
What side of the lcd should face the bulb?
My guess would be the back side because the lcd backlight shines through that one... but on the other hand: my lcd has a silverish shine on the back so a lot of light might be reflected back??

Do other people also have lcd's with a shiny silverish back? What did you do? (back to bulb/ front to bulb)