I just started looking into the DIY projector project. It looks like a great project and I'm amazed at the number of resources I've found so far. Just have a few question to get me started, as I'd like to build a decent one the first time.
1) Which method is best? I've seen a lot of info on stripping an active matrix display down to just the glass and projecting light through it. I've also seen some design that bounce light off a display. Which method achieves the best results?
2) I'd like to keep the size small, but do not want to sacrifice quality. How small a screen can I find for XGA? Are there good values for that?
3) Has anyone had good success with the white light LEDs? I'd like to keep the heat and power down. I was considering make a panel of LEDs about the size of the screen, and with very little heat, I could place it a lot closer to the screen. My main concern is getting enough lumens from it. Can it be done? Does it need to be done? If I use ones with a very lower viewing angle, do I still need 4k lumens or can I use less since most light will go straight to the display and lens?
Thanks for all your help, hoping to make a groovy projector. If I get the LEDs are possible, I might be able to make extras for others.
1) Which method is best? I've seen a lot of info on stripping an active matrix display down to just the glass and projecting light through it. I've also seen some design that bounce light off a display. Which method achieves the best results?
2) I'd like to keep the size small, but do not want to sacrifice quality. How small a screen can I find for XGA? Are there good values for that?
3) Has anyone had good success with the white light LEDs? I'd like to keep the heat and power down. I was considering make a panel of LEDs about the size of the screen, and with very little heat, I could place it a lot closer to the screen. My main concern is getting enough lumens from it. Can it be done? Does it need to be done? If I use ones with a very lower viewing angle, do I still need 4k lumens or can I use less since most light will go straight to the display and lens?
Thanks for all your help, hoping to make a groovy projector. If I get the LEDs are possible, I might be able to make extras for others.
Hi
I havent finished my projector but I should be able to help 🙂
1) Have never seen light bouncing off the display, only through so cant really help on that but passing light through seems to be affective
2) The 7" lilliput xga lcds are very popular as they have 1,152,000 pixels and they are widescreen. But the 14"+ will have a better quality picture overall, yet if you see results of the 7" projectors they are really quite impressive
3) LEDs well you can get them and work well on small 5" ps screens at about 40-50" projected (i think thats what i read in a post) but it still wouldnt be very bright
if you go for a 7" or 5" projector then you could get away with a 175 or 250w lamp and have 2 120mm fans running at half speed over it and have it cooled nicly (hillbilly did this and it worked great)
Overall you are looking at what i wanted, small high quality and not pumping out the heat, and the only problem i had was i got a 400w bulb which really pumps the heat out
Hope this helps 🙂
I havent finished my projector but I should be able to help 🙂
1) Have never seen light bouncing off the display, only through so cant really help on that but passing light through seems to be affective
2) The 7" lilliput xga lcds are very popular as they have 1,152,000 pixels and they are widescreen. But the 14"+ will have a better quality picture overall, yet if you see results of the 7" projectors they are really quite impressive
3) LEDs well you can get them and work well on small 5" ps screens at about 40-50" projected (i think thats what i read in a post) but it still wouldnt be very bright
if you go for a 7" or 5" projector then you could get away with a 175 or 250w lamp and have 2 120mm fans running at half speed over it and have it cooled nicly (hillbilly did this and it worked great)
Overall you are looking at what i wanted, small high quality and not pumping out the heat, and the only problem i had was i got a 400w bulb which really pumps the heat out
Hope this helps 🙂
Hi,
The lilliput displays are not XGA, so don't consider them if you want resolutions in that region. They are 800x480 iirc, fine for DVD, not so appropriate for other use (HD, PC etc etc.).
I believe there was talk of a 10" XGA pannel some time ago, have a search of the forums. Also search regarding the LEDs, I'm afraid the arguements presented will probably put you off the idea...
Quin.
The lilliput displays are not XGA, so don't consider them if you want resolutions in that region. They are 800x480 iirc, fine for DVD, not so appropriate for other use (HD, PC etc etc.).
I believe there was talk of a 10" XGA pannel some time ago, have a search of the forums. Also search regarding the LEDs, I'm afraid the arguements presented will probably put you off the idea...
Quin.
Why is it that answers always cause more questions? 🙂
Thank you both. I've been doing some more reseach and think I might be starting to get a handle on some of it. Ideally I'd like this for a HTPC so a VGA input would be needed. I think in those circumstances, XGA is a good resolution to aim for. Am I correct in believing that I will not find an XGA display in the 7-8" range? How big would I have to go to do so?
I also have a couple questions about lens and reflector requirements. There doesn't seem be a consensus as far I can tell on what all is needed.
If I stick with a 7" screen, do I need a condensor?
Some people use a Fresnell lens before and after the LCD, is it needed? why/ why not etc.
Is MH still the best light source?
Looks like 300mm focal lengths are best for the lens and Fresnell yes? Does the fresnell to LCD distance matter much?
Awesome stuff! I think my first task will be choosing an appropriate LCD. So now the question, do I build a projector, or rebuild the vintage 1941 cabinet radio someone gave me? 😉
Thank you both. I've been doing some more reseach and think I might be starting to get a handle on some of it. Ideally I'd like this for a HTPC so a VGA input would be needed. I think in those circumstances, XGA is a good resolution to aim for. Am I correct in believing that I will not find an XGA display in the 7-8" range? How big would I have to go to do so?
I also have a couple questions about lens and reflector requirements. There doesn't seem be a consensus as far I can tell on what all is needed.
If I stick with a 7" screen, do I need a condensor?
Some people use a Fresnell lens before and after the LCD, is it needed? why/ why not etc.
Is MH still the best light source?
Looks like 300mm focal lengths are best for the lens and Fresnell yes? Does the fresnell to LCD distance matter much?
Awesome stuff! I think my first task will be choosing an appropriate LCD. So now the question, do I build a projector, or rebuild the vintage 1941 cabinet radio someone gave me? 😉
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