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Alien
Apprentice
Canada
149 Posts |
 Posted - Oct 11 2003 : 10:51:31 AM
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Would this work ? Using a fresnel lens to project the tv screen on the wall? It says i would get a slightly blurred image but still good and pretty big.. http://bigscreentv.20m.com/ < --
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Andrew
13/m/Canada
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n/a
DELETED (Inactive)
2 Posts |
Posted - Oct 11 2003 : 1:42:30 PM
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I ordered the lens you mention from
American Science Supply and Surplus if I
remember correctly... neat idea and a valid
concept, with the problem being a lack of
brightness. A TV just doesn't put out enough
light to be projected and still maintain a usable
light level. Also, you have to plave the TV on
it's top to get an upright picture. I took the
time to paint two halves of a cardboard box
black, one inserted into the other and they did
"telescope" for focussing. Like I said, neat
idea, solid concept, but TV's aren't bright
enough. BUT, a fresnel lens is neat to play
with in other ways... using the sun you can
generate MEGA heat... toasty ants anyone?
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cirvin
Nobel Prize Winner
USA
1542 Posts |
Posted - Oct 12 2003 : 8:28:18 PM
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i did the xact thing from this sam site. it works fine. it is alittle dim and the focus is really touchy but if you take ur tim and build it properly, it will preform fine. don't tip your tv over. instad, tak it apart, and you will s a coil on the neck of th tube. there should be 4 wires coming from it. cut 2 of them. if all you s on the screen is a line runing horozontally or vrtically , put the wires bcak where they cam from xcpt revrsd. do that with the other two
at last!!!
Edited by - cirvin on Oct 12 2003 8:31:34 PM |
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Aaron Cake
Administrator
Canada
6718 Posts |
Posted - Oct 14 2003 : 10:14:38 AM
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I've seen a demo of this, and it was pitiful. Really, really pathetic. I personally wouldn't waste my time...
As for pulling the field wires to make the TV brigher...That will work, but will quickly burn out the tube.
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cirvin
Nobel Prize Winner
USA
1542 Posts |
Posted - Oct 14 2003 : 4:48:57 PM
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no no no, you revers the feild to invert the imag so it comes out fine on the screen
at last!!! |
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Alien
Apprentice
Canada
149 Posts |
Posted - Oct 14 2003 : 8:26:01 PM
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Well, i was sure you're gonna think its rather stupid, but i'm gonna try it anyways. Almost all TVs have some sort of pot in the back of it near the flyback where you can make it brighter and i wouldnt care if it burns it out faster cuz i got the tv for free and it's crappy anyways... I'm gonna make it probably next week if i can get ahold of a fresnel lens.
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Andrew
13/m/Canada
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Aaron Cake
Administrator
Canada
6718 Posts |
Posted - Oct 15 2003 : 10:57:34 AM
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Well, I don't think it's stupid. But I do think that if you expect to get any good use out of it, you will be disappointed. It's a neat experiment, but nowhere near practical to use.
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Alien
Apprentice
Canada
149 Posts |
Posted - Oct 15 2003 : 8:46:48 PM
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heh, okay... I'm doing it anyway, maybe it'll work. What have i got to lose.. i got plenty of time that i spend on the computer wasting it anyways :p lol
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Andrew
13/m/Canada
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cirvin
Nobel Prize Winner
USA
1542 Posts |
Posted - Oct 16 2003 : 4:07:51 PM
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i would take a small handhld lcd tv, open it up, remove the floorcnt back from th lcd, then put a high wattag bulb bhind it(lik 300w) and use the lense from there
at last!!! |
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Alien
Apprentice
Canada
149 Posts |
Posted - Oct 16 2003 : 4:39:24 PM
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hmm, how will i be sending the video from the tv and dvd player to the lcd? Controller?!?!
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Andrew
13/m/Canada
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BEatonNo1
Nobel Prize Winner
USA
1133 Posts |
Posted - Oct 16 2003 : 6:26:50 PM
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usually they have some sort of aux in. however, that is a nifty idea. but I would use something bigger than a 300 watt bulb.
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Aaron Cake
Administrator
Canada
6718 Posts |
Posted - Oct 17 2003 : 11:40:55 AM
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quote:
i would take a small handhld lcd tv, open it up, remove the floorcnt back from th lcd, then put a high wattag bulb bhind it(lik 300w) and use the lense from there
Now that's an interesting idea...Even just an overhead projector might do it if you place the LCD over the bottom side of the lense...
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BEatonNo1
Nobel Prize Winner
USA
1133 Posts |
Posted - Oct 17 2003 : 4:00:01 PM
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my old high school has some devices like that. not shure how they look on the wall though
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cirvin
Nobel Prize Winner
USA
1542 Posts |
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Aaron Cake
Administrator
Canada
6718 Posts |
Posted - Nov 12 2003 : 3:00:28 PM
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That looks very cool. I'll have to take a close look when I have time.
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cirvin
Nobel Prize Winner
USA
1542 Posts |
Posted - Nov 12 2003 : 6:14:09 PM
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one guy made a wall mounted unit that is pretty impressive, but there could be alot of improovements made like a reflector and a smaller bulb, and space between the fresnel and the lcd. i am going to build one and have it swing down from the rafters in my attic
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Topic |
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Converting normal tube TV to a projection
