DIY Video Projector

[John_in_Az]

see also

http://www.physics.umd.edu/deptinfo/...demolst.htm#b1

for info on optics, and properties of light !

Cheers !!

[Bitch]

**** that free webspace and it's transmit limits, here are the pics hosted on my isp.

[Gunawan W]

hi all,
here some links about high output fluorescent lamp.
It will make more choice to select than from LOA only.
The lamps are: PL compact fluorescent lamp 42 watt, triple output with initial lumens=3200 (Philips), use
3 units will produce 9600 lumens!
Don't forget use good reflector to make narrow angle light beam.

http://www.lighting.philips.com/nam/...s/P-3541-C.pdf

http://www.con-techlighting.com/pdf/compact_rl132v.pdf

http://www.con-techlighting.com/pdf/compact_rl132v.pdf

http://www.sportlite.com/MX-Series.htm

or you can search yourself with keyword:

t 42 fluorescent lamp triple tube high output

see you.

[gmshroll]

Originally posted by Bitch
**** that free webspace and it's transmit limits, here are the pics hosted on my isp.

Have you been at the crack pipe?

"Here is the toilet with Fresnel attached"

[Flagre]

I was doing some basic calculations and somehow I came to the same conclusion. If you decide to display an image, lets say 120x90cm on the wall. Then it's the same what type of display you choose, if you just vary the magnifier. With a 1024x786 screen at 2", you would do a x30 magnification. With a 10" at the same res you would do x6. (based on the same distance and lenses of cource)The only problem is that the box need to stand closer to the display wall, but that shouldn't be a problem. The box will also be quite big if you use a 10" screen. Concering the light, you need to spread the lumens/cm more on the 10" screen and you need a bit more lumens to be on the safe side. With good reflectors, and some more calculations of some parabolas and their junction points, making an reflector yourself, this shouldn't be a problem...it's more in the reflectors than in the lamps it self. Of cource you need a lamp of good q, but with the parabola contructed right, it would need less q lamps to get the same result, ne1? Have you guys tried some automobil headlamps, thoose that you switch on when you need a lot of light. Just using the frame and the reflektor I think it would be a great test lamp, and they cost almost nothing, and can run of a basic pc supply.

Wonder why I write all this? It's seems like thoose 10" displays are a lot cheaper than thoose 1" and 2" high res.

What do you guys think of this?

[andrewjames1000]

Hi Everyone

Been browsing for a while and thought I better share some ideas.

On a light source I think you should look into a halogen bulb called EVD which is 36V 400w. These can be found on the internet for about £10/$10. I'm no electronics expert but I think it would be easy to build a circuit for it. These bulbs can last for about 100hours so should still be quite good value. They are about 4000-5000 lumens.

Another quick thought for someone being really cheap would be to use a very very bright light source that is actually free. The sun! It might be possible for those of you who live in sunny california etc (not me in Leicester, England) to black out a window using black spraypaint or similar leaving a small space which you attach your projector box to. With a suitible location I think this could be possible. You might need a lense or mirror outside or something.

Final thought for those of you with laptops to sacrifice you could perhaps get a USB tv card for approx £60/$60. This would be all you need to get video on the screen if you can keep it connected to the main laptop unit.


Andy

[John_in_Az]

Yeah, nice idea..but my old laptop doesnt have usb...guess ill need a usb port + usb capture card...anyway.......

Hope you all are making progress ?

As soon as i get my lcd panel..ill get started.
Have a couple bids on ebay now.

Later,

John

[fender4]

Hey guys,

I looked into the laptop LCD option a while back...I couldn't resist $30 for a 800X600 LCD. I looked into somehow getting a video signal into one of the many raw laptop panels available on the internet now, and it turned out to be more trouble than it is worth. I wrote Tomi Engdahl, an expert on video signal converters, among other things, and he said (paraphrasing):

"Technically, it is possible.
Practically, it is so complicated that this is not worth it for any
homebuilder or even professional to do unless there is huge
market for this kind of converter for this particular display
and somebody will pay for the development."

I then asked, "Are the connection pins the same on a laptop screen as they are on a standard CRT monitor?"

"No. Pin functiolities are completely different in laptop LCD and
in CRT monitor. And there are at least half dozen different
proprietary interfaces used in laptop LCDs (no real standards on those)."

Check out these links for more info:

http://www.hut.fi/Misc/Electronics/c...video2vga.html
http://www.epanorama.net/links/videochips.html
http://www.epanorama.net/links/video...tml#converters

So that's where I stand right now with the laptop LCD idea. On the other hand, a complete laptop computer with a TV card and the back removed from the LCD would be an option, although it seems a little excessive. If you have access, though, go for it.

I am still thinking about getting the 2.5" A.N.D. LCD from Allied Electronics. The price is reasonable, and I like the small size (so I can use a smaller, cheaper projection lens assembly without a fresnel lens). Resolution is low, but it's a start

Lots of new light ideas...keeps things interesting. I'm no authority on it, but I think that a color temp (K) of around 6000K would give the best "white" light. Anything below it would start looking slightly red. Also, fluorescent bulbs shift toward the red spectrum (lower K) with age.

Sorry I haven't had time to actually order the parts and start assembling this thing. I'm waiting for a break in school to concentrate on it. Hopefully soon.

-f4

[John_in_Az]

lol ...well look more trouble then its worth...converting a laptop monitor to accept video signals is too complicated, and the driver boards are more then just buying a video lcd, or project lcd.

Oh well, just thinking outside the box here.
Hope my ebay bid holds up for the lcd panels..

John

[Type-E]

Yeah, don't make problem more complicated. The current problem is to how fresnel lens should be place to obtain optimal quality.