This began recently as my kids wanted a bigger TV.
Plain and simple.
We recently got a new TV so another for the kids room was out of finances and I thought ok make a projector. I'd used the very basic technique a while back to paint an outline to a picture, enlarged on a wall, so I had a very basic grasp of the concept - light source -> image -> lens -> screen (I said basic 😛 )
I did a little research - fresnel lenses, triplets etc and due to being in the UK found it pretty hard to find these supplies at a decent price - it actually worked out much cheaper to buy an OHP and butcher that.
I sourced a suitable monitor @15" - that's been stripped down to the necessaries.
I sourced a cheap OHP on eBay (hopefully suitable - if anyone can give me some feedback that would be great - it's a Elite Tutor 2000). That's being shipped at the moment so I have a few days before I can look at that.
I'm pretty handy so I'm confident with the construction of the enclosure and the electronics are no problem.
I wanted this to be self contained, by that I mean an onboard media hub - I chose a cheap HD media player - basically a card reader with a vga (the monitor is VGA only) out.
So that's where I am so far.
Now I need some help if anyone wants to chip in 😛
I would like to strip the OHP right down and build a custom enclosure, I'm expecting to have to replace the bulb, I'd like however to replace the entire light.
I'm assuming to go by lumens not watts and I found a 10w LED security floodlight that it said to kick out 800 lumens
IP65 PIR Classic LED Floodlight 10W 20W 30W Security Flood Light Garden Outdoor | eBay
a viable source? If no can I get some solutions 🙂
Also I'm assuming the OHP will come with two lenses glued together..am I good to leave these stuck together and then placed between the light source and the LCD.
And finally (phew) I'm still unsure as to do I need another fresnel lens between the LCD and the focus/triplet (sorry still not too sure on terminology yet) lens?
Thanks very much for any help and as soon as I make some progress I'll post it here.
Plain and simple.
We recently got a new TV so another for the kids room was out of finances and I thought ok make a projector. I'd used the very basic technique a while back to paint an outline to a picture, enlarged on a wall, so I had a very basic grasp of the concept - light source -> image -> lens -> screen (I said basic 😛 )
I did a little research - fresnel lenses, triplets etc and due to being in the UK found it pretty hard to find these supplies at a decent price - it actually worked out much cheaper to buy an OHP and butcher that.
I sourced a suitable monitor @15" - that's been stripped down to the necessaries.
I sourced a cheap OHP on eBay (hopefully suitable - if anyone can give me some feedback that would be great - it's a Elite Tutor 2000). That's being shipped at the moment so I have a few days before I can look at that.
I'm pretty handy so I'm confident with the construction of the enclosure and the electronics are no problem.
I wanted this to be self contained, by that I mean an onboard media hub - I chose a cheap HD media player - basically a card reader with a vga (the monitor is VGA only) out.
So that's where I am so far.
Now I need some help if anyone wants to chip in 😛
I would like to strip the OHP right down and build a custom enclosure, I'm expecting to have to replace the bulb, I'd like however to replace the entire light.
I'm assuming to go by lumens not watts and I found a 10w LED security floodlight that it said to kick out 800 lumens
IP65 PIR Classic LED Floodlight 10W 20W 30W Security Flood Light Garden Outdoor | eBay
a viable source? If no can I get some solutions 🙂
Also I'm assuming the OHP will come with two lenses glued together..am I good to leave these stuck together and then placed between the light source and the LCD.
And finally (phew) I'm still unsure as to do I need another fresnel lens between the LCD and the focus/triplet (sorry still not too sure on terminology yet) lens?
Thanks very much for any help and as soon as I make some progress I'll post it here.
A little more research has lead me to getting a 100w chip LED to replace the 10w in the lamp I posted previously.
Sorry that you're not getting feedback but you have to remember this is an audio site and projectors are a very small part of it. Not trying to scare you off but are there not other sites more in tune with what you are hoping to achieve? I wish you luck either way.
Hi there. I am also a newbie projector builder and have recently build my first DIY projector though it is not that bright but still watchable. I am using a 128w led light for light source. There are a lot of adjustments to be made to achieve what I want to achieve.
LED's aren't the way to go just yet. They won't be bright enough. Check the stickied threads for more info on why and what you should use . Also you can access portions of the old Lumenlab site through the Internet Archive (The Way Back Machine). From there you can download the guide to making DIY projectors gif. I'll see if I can dig it up. If I can I'll post it here in a new thread.
Unfortunately, when Lumenlab went down it set off a chain reaction that eventually took all the other DIY projector sites with it.
Unfortunately, when Lumenlab went down it set off a chain reaction that eventually took all the other DIY projector sites with it.
Thanks - appreciated. LED tech has come along way in recent years the LED I ordered is 100w/8000 lumens the original bulb was 250w/3600 lumens...could you explain why you think the LED won't be bright enough..what am I missing?
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Hi
1. The 10W LED won't work as it won't be bright enough. The 100W LED won't work as it has a WAY to big emitting surface area and that will give you two problems; for one you won't be able to get the full image of the LED through the projection lens (assuming you go with the OHP triplet and fresnels) as the fresnels are most likely 220mm FL and 330mm FL which means together they will effectively magnify the image of the LED die (there is a way to calculate by how much, I just can't remember) thus you will not capture all of the light from the LED, unless you can find a larger lens. Second problem, due to having such a large emitting area you will effectively have several very small point light sources, meaning you will be projecting the same pixels on the LCD on different points on the screen (although very very close together) which will result in a much too blurred image, especially in the corners. Phew 🙂
2. You should leave the OHP fresnel lens untouched and go with an unsplit design where you have the lamp - fresnel - lcd - lens. You don't need another lens after the LCD as the first lens in the OHP sandwich collimates the light to go through the LCD and the second one condenses it to reach the triplet lens.
3. For the light I'd strongly suggest you look into metal halides as they have a great lumen to watt ratio, good colour and great life of over 10000 hours. You could go with a 250W double ended one. These put out an average of 20000 lumens and all that from a 25mm by 10mm insanely bright arc. Just make sure you don't get the ones they use for aquariums as they have a much too high kelvin temperature of 10000 Kelvins +
When Lumenlab was still kicking about I saw some builds with amazing results with 250w metal halides and even with optics as simple as the ones used in OHP.
4. Good luck
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