So i'm really wanting to try this, but i'm rather confused. Here is what i've been able to gather so far on the assembly - this would be a long rectangular box from back to front:
cup shaped metal reflector -> light -> UV glass -> fresnel lens (looks like a sheet of plastic) -> another fresnel lens -> lcd - > some space and then the front round lens; (cooling would be installed as well)
Is this correct? And i'm trying to see if a few assumptions are correct:
1. I would need to make the box about 8-10" wide/tall to give space for mountings, and to allow airflow around each component
2. The size of the fresnel lens(es if two are necessary) are irrelivant as long as they are at least the size of the LCD
3. Any light source will work as long as it is bright enough, LCD's are likely not a good option, and I shouldn't need a 400watt+ light for a small projector.
4. I'm aiming for something between 32 and 42 inches, this will be ceiling mounted somewhere between 4 and 6 inches away. I do need to tilt the LCD to prevent a misshapen or improperly balanced screen, that much is obvious.
But I am clueless on the measurements. Should I just make a super long (say 1.5 feet or so?) wood box and start placing components to try it out? I have no idea where to start with lenses, I heard about someone who got lenses at office depot (i'm going cheap) although i'm kicking myself now for not buying an old slider projector for $1 that I saw at a garage sale. I've seen a few calculators but in all honestly i'm clueless. Any thougts on how to begin? I've read a few beginners guides but I still don't seem to be any closer to an answer.
cup shaped metal reflector -> light -> UV glass -> fresnel lens (looks like a sheet of plastic) -> another fresnel lens -> lcd - > some space and then the front round lens; (cooling would be installed as well)
Is this correct? And i'm trying to see if a few assumptions are correct:
1. I would need to make the box about 8-10" wide/tall to give space for mountings, and to allow airflow around each component
2. The size of the fresnel lens(es if two are necessary) are irrelivant as long as they are at least the size of the LCD
3. Any light source will work as long as it is bright enough, LCD's are likely not a good option, and I shouldn't need a 400watt+ light for a small projector.
4. I'm aiming for something between 32 and 42 inches, this will be ceiling mounted somewhere between 4 and 6 inches away. I do need to tilt the LCD to prevent a misshapen or improperly balanced screen, that much is obvious.
But I am clueless on the measurements. Should I just make a super long (say 1.5 feet or so?) wood box and start placing components to try it out? I have no idea where to start with lenses, I heard about someone who got lenses at office depot (i'm going cheap) although i'm kicking myself now for not buying an old slider projector for $1 that I saw at a garage sale. I've seen a few calculators but in all honestly i'm clueless. Any thougts on how to begin? I've read a few beginners guides but I still don't seem to be any closer to an answer.
Yes, correct for an "unsplit" design. A "split" design would have the LCD sandwiched between the two Fresnels and then the projection lens.
The box only needs to be big enough to fit all of the parts. There is no standard size unless you buy a kit from some of the different websites. It's always better to build the box last, after you have assembled the optics so you know what size you need.
Kind of. They do have to be bigger than the LCD but not by much. Between a 1/4 and a 1/2 inch is plenty of overlap all the way around.
Yes but every light source has its positives and negatives. The negatives usually being heat and power consumption.
People have had success with LED's but it takes a lot of time and research. Screwing in a bulb in less than 10 seconds is a lot easier in some people’s minds. LED's are the future but the question is near future or far.
General rule of thumb is up to 400 watts for an LCD under 15", usually 100 - 250 watts. 400 Watts for an LCD over 15".
I don't know how big a PS One screen is but if it is 10 inches or less just buy an overhead projector. They have all of the optics that you would need. Some don’t have reflectors so you would have to check to see if the one you purchase does but if it doesn't it’s no big deal. You can buy or make one. Check out your local schools for a surplus overhead projector. The throw would be longer than 4 - 6 inches for a 32 inch screen. It probable would be closer to 2 -4 feet of throw to get a 32 - 42 inch screen. Besides, that short of throw would give you a horribly distorted picture. The picture would look more like a triangle than a rectangle from the keystoning.
Zaner21
Ah I apologize I messed up on that point as well 😉 I mean 4-6 feet as far as the mounting distance from the screen. I would probably end up either ceiling mounting this or maybe even placing it on top of a dresser or night stand. I'd use it as an occasional DVD player screen in my bedroom. I've already got a normal TV and in there - this would be more of a learning experience and a sort of "proof of concept" design to convice the wife that a DIY projector is a good idea 😛
The PSone screen is 5" approxmately, it's a rather small and low resolution panel, and i'd probably just use a 120-175 watt halogen bulb just to try out and see how it works. I'm not sweating any of the wiring details, that should be no big deal.
I appreciate the info, should be enough to get me started! I'm doing the usual saturday garage sale hutning tomorrow so maybe i'll chance upon a used projector!
The PSone screen is 5" approxmately, it's a rather small and low resolution panel, and i'd probably just use a 120-175 watt halogen bulb just to try out and see how it works. I'm not sweating any of the wiring details, that should be no big deal.
I appreciate the info, should be enough to get me started! I'm doing the usual saturday garage sale hutning tomorrow so maybe i'll chance upon a used projector!
Well I found a couple of slide projectors, I know the focal length on these are going to produce small screens (15-20" at best) but should be enough for proof of concept. Going to start building it in a shoebox to test fit, and if all goes well i'll make a nice wood design and get the proper cooling and wiring. Will post pics as soon as I make some progress!
Actually, to specify, the two lenses I have are both f3.5, 4" and 5" respectively. So at my appropriate lengths we are talking maybe a quality image of 10-20". I'll look into buying a better lense for this box before the final build if it goes as planned, i'll make the wood box extra long and chop down the length as needed when I get a quality lens.
Actually, to specify, the two lenses I have are both f3.5, 4" and 5" respectively. So at my appropriate lengths we are talking maybe a quality image of 10-20". I'll look into buying a better lense for this box before the final build if it goes as planned, i'll make the wood box extra long and chop down the length as needed when I get a quality lens.
I have projection! It turns out that I was totally overestimating the requirements. My current list:
$3 2'x2' plywood (lowes)
$9.50 PSone LCD (kmart clearance)
$9 office depot page mangifier (this makes minimal difference)
$8 flea market slide projector - salvaged the lense (F3.5, length 4")
$1.25 standard light bulb socket
$10 Flourscent flood light bulb 40w ("125w") with built in reflector
Total cost so far: $40.75! I expect around $15-20 in misc other costs (DC fan that runs off of psone lcd power, connectors for video and power switch, etc)
Since there are no pics yet - the entire thing measures 14.25"x6"x6"
I thought i'd get minmal results with this cheap setup, but so far it's looking great. With the lights off I get decent brightness and the box stays rather cool. The big misconception I had was that i'd need a super bright $200 light kit or whatever to get the job done (and I will be using one when I build a 15" LCD projector) and it's just not true for small projectors.
PICS ARE COMING! (but after I finish working on it for the night)
$3 2'x2' plywood (lowes)
$9.50 PSone LCD (kmart clearance)
$9 office depot page mangifier (this makes minimal difference)
$8 flea market slide projector - salvaged the lense (F3.5, length 4")
$1.25 standard light bulb socket
$10 Flourscent flood light bulb 40w ("125w") with built in reflector
Total cost so far: $40.75! I expect around $15-20 in misc other costs (DC fan that runs off of psone lcd power, connectors for video and power switch, etc)
Since there are no pics yet - the entire thing measures 14.25"x6"x6"
I thought i'd get minmal results with this cheap setup, but so far it's looking great. With the lights off I get decent brightness and the box stays rather cool. The big misconception I had was that i'd need a super bright $200 light kit or whatever to get the job done (and I will be using one when I build a 15" LCD projector) and it's just not true for small projectors.
PICS ARE COMING! (but after I finish working on it for the night)
To clarify on lighting - I mean that the brightness is decent in the dark. This is going to be a causal night time use project, obviously it's rather weak in normal light, where as a normal projector is probably not so bad in the day time.
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