DIY Projector? I figured I take an LCD screen, remove the diffusal

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You're forgetting that you need one or more lenses between the light source and LCD.

Also your LED needs to be as close to a point source as possible. Don't use a board with multiple LEDs spread out on it.

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Put LCD on pic related.

>>1122824
Don't forget cooling. LCDs don't like to get hot. And since they work by selectively blocking light, they inherently generate heat. If you pass enough visible light through one to produce a large, bright image, it will get hot.

This is why large image projectors use DLPs (lots of tiny movable mirrors). The DLP doesn't block the light, it diverts it to a surface that absorbs it. That surface gets hot, but it isn't sensitive to overheating and can easily be cooled.

>>1122824
AFAIK, 'color' LCDs basically let fuck all light through, they used to use monchrome panels (either 3 of, for RGB) or switch colors quickly, or, do it with mirrors (DLP).

Monochrome LCD panels let through a shitload more light, prob being, they are daf to buy. Then, you get arguments about the color balance of LEDs, etc. Basically, all aint as simple as it seems, but, someone may have better info, mines prob way outdated.

>>1122865

just saw this video today:

https://www.youtube.com/watch?v=hlLiT3-Ib-o
watch at around 8mins, there they build exactly what you are saying...
they got the overhead projector for 15€ on ebay

LCD projector projects were a big deal a few years ago until people got wise to the idea that they're complete shit coz you can only watch them in pitch dark rooms, and that a commercial projector is 1000x better.

>>1123065
this.

I've played with the idea at that time but then I've run into second hand high-end projector for a good price and never looked back. Nowadays projectors are dirt cheap, but if you want to go DIY route, get commercial one without a lamp and stick LED module in it

>>1123051
is this true? main grumble about dlp was the color smear from the wheel, i didn't think single lcd's used a wheel. it would be ~3x more light for ~1/3 of the time plus blanking perhaps?nightmare.

>>1122865
yeah look at that great output wow

>>1123065
>>1123065
>>1123097
are you trying to say they have inherently bad contrast?

Ten years back I was planning to make one, using an asshueg metal halide lamp. LEDs have come a long way but I dunno if they're bright enough still.

>>1123366
They are.

>>1123377
For a dark room, yes.

>>1123379
just give me one reason why diy projectors are not bright enough.

>>1123065
I'd say this too, OP

I got myself an EPSON 2045 for $450
Best purchase i have done in the past few years.
Now looking forward on to making a dark matte high gain screen.

>>1122824
Use an overhead

>>1122824
Check out

http://www.instructables.com/id/DIY-2k2560x1440-Beam-Projector/

I am seriously considering DIY for my next projector for a 1440p screen or even 4k if a lcd with controller is finally released.

The two older led projectors I already have probably will also provide casings/parts/lenses to make it easier.

I will stick with my current 720p projector for a year while waiting on the 4k screens.

>>1122824
it's a meme. I tried it but it works like shit. I have a few reasons why it doesnt work. firstly you need to work with sub par optics, second, LCD panels have contrast coatings, most decent panels with a high color rendering index have tinted glass or tinted polarizing layers so you cant remove the thing that causes a massive loss of light, you cant use an LED because they're too big physically, for projection you need a point light source. the 100W leds are massive and you need a custom optical fish eye element for them to work.