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naitogunjin
Hello everyone,
I have decided to embark on the DIY experience and build me a projector.
So i bought the parts i thought i needed but i soon found out they just were not working.
I'm a little confused on the design as well. I probably should have done a little more research from this website before i jumped in.
Anyways i have an LCD monitor which i have taken apart and the dimensions are 11" tall and 14" wide.
I have a 1:3,5 230mm projection lens and i bought a Fresnel lens which turned out to a piece of crap that looks like something you would get out of a cereal box!
So i need to buy the right one, oh and i also found out that i need two Fresnel lenses more clarity on that would be good as well.
I know the Fresnel lenses need to be at least the same height as the LCD but what about focal length?
Do i need a certain focal length for my lenses? Is the smaller the better? I don't know!
So my first question is what Fresnel lenses do i need to buy for my LCD and projection lens?
Second question is on the Design. Tell me if im right.
So you have a light source it shines through the combination of two fresnel lenses which condenses the light down to a point. You stick an LCD in front of the frensel lenses and the picture off the LCD along with light shrink down to a point, stick a projection lens on that point and it projects your image and the light on to a wall.
I think i have the basic concept right i just feel like i have something backwards.
If anyone could help that would be great!
Peace out!
naitogunjin
I'm thinking about buying two Fresnel lenses from BHLENS.com
Product:BHPA220-2-5
Size: 310*310mm
Thickness: 2mm
Material: PMMA
Groove pitch: 0.5mm
Focal length: 220mm
Price: $8.000 hopefully that means $8

and

Product:BHPA330-2-1
Size: 310*310mm
Thickness: 2mm
Material: PMMA
Groove pitch: 0.5mm
Focal length: 330mm
Price: $8.000

Is this a good decision considering my other parts?
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