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REAR PROJECTION TV HARVEST! lots of pic's!

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Stephen j gilman

Guest
Hello everyone on LPF! ;b

Today I got the pleasure of destroying a non-working tv! But first... It's time to open it up, rip out all it's guts, and show what I have obtained!!! I took alot of pics from start to finish! ;b


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Stephen j gilman

Guest
I got 3 glass lenses, and 6 plastic lenses. I also got a huge fresnel lens! And a weird grate film. The glass lenses focus a laser to I super tiny point. Any ideas on what I can do with this stuff?

I was so sad. I wanted a PBS cube so bad, but no cube for me!
 

Benm

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The fresnell lens will prove to be fun in summertime - use it to start your bbq!
 

vk2fro

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yes get that fresnel lens out into the sunlight and burn down a tree stump. Those things can turn bright sunlight into a fairly powerful (but poorly collimated) burning beam, badder than any laser pointer! :)

The best way is to use that massive mirror pointed at the sun so it reflects on a 45° angle (i.e. parallel to the ground). Put the fresnel lens in front of it to collimate (badly) the sunlight. Place a beam stop a few feet back, and start introducing items (with tongs silly) into the super hot beam. :)
 
S

Stephen j gilman

Guest
I burned stuff all day! I just hold it over something and poof! I wanted a PBS cube so badly... :,( I would trade all my lasers and lenses for one! What can I take cool optics out of? Like cubes, phr's, ect?
 
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^PBS cubes are like $50. They are in many sleds as well, but they're teeny, harder to work with, and have higher losses.

I just thought I'd point out there is a difference between collimation and focusing. By itself in sunlight, A Fresnel lens does the latter.
 
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I never understood why people bought those rear projection TVs in the first place. Their pictures were always total shit. I guess they were the poor man's "big screen TV."
 
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At sea level... the sun throws about 1kW/m^2 at us.

I suggest you start playing with that fresnel lens. EXCELLENT survival tool.
Boil water, cook (solar oven), start fires, signal, welding, lots of electric (with a solar cell)...

I wonder if you could get a second lens to collimate it and then a third proper lens to send it down to a super fine point... you'd might have to use antireflective fused quartz or saphire lenses due to the high power levels. It'd be totally worth it though. Even with an overall optical efficiency of 40% that's like 400W focused to a point. I would make Lava.
 
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I never understood why people bought those rear projection TVs in the first place. Their pictures were always total shit. I guess they were the poor man's "big screen TV."
It is incredible to see how TVs evolved from this to oled and lcd TVs,. :yh:
 
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I never understood why people bought those rear projection TVs in the first place. Their pictures were always total shit. I guess they were the poor man's "big screen TV."
I have one! It's a Hitachi 52" and the picture is quite good, the sound is better than my flat screen 37" Vizio and at the time the Hitachi was $1300. So I must be a poor man.
 
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I have one! It's a Hitachi 52" and the picture is quite good, the sound is better than my flat screen 37" Vizio and at the time the Hitachi was $1300. So I must be a poor man.

Maybe the ones I saw were the cheap "big screen" TVs that people bought because they just saw "big" and not "quality," like those giant CRT TVs that were bulbous and horrible.
 
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^^^Mine is about 9 or 10 years old. Still works great, but you are right you have to watch what you buy. I have a friend that repairs TVs and I usually ask him what to buy when I am in the market for one. When I got my Hitachi he recommended that particular TV and I haven't had any problems with it. It has surround sound with great bass. It doesn't have as good of a picture like my Vizio, but for it's age it is still good.
When I bought it the selection wasn't that great and the plasmas were new to the market and was advised to stay away from plasma TVs.
 




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