Introduction: Salvaging the Fresnel Lens From a Rear Projection TV
I was thinking of DrSimons awesome instructable the other day when i spotted a discarded TV on the road side.
Since it was garbage day, and my wife stated in no uncertain terms that it had to go "that day", I decided to make a quick video on how to get the screen out. I also salvaged a nice first surface mirror form the cabinet for a never to be made future laser instructable.
So enjoy this brief video of me looking disheveled and fat as I rush to disassemble the TV before the garbage truck comes.
21 Comments
1 year ago
These comments, though old, hurt my eyes. The worst being, "the liquid is mineral oil". The liquid is ethylene glycol which was in old antifreeze and kills animals that drink it. Saying things without being educated is a good way to get a person or their pet killed. This is why people should be screened before they can have kids. I'm sorry but I don't understand why anyone would spout that out when it could be fatal to a life.
11 years ago on Introduction
TUA, with that front surface mirror you can make a 3D mirror array for photograph.
Reply 4 years ago
updated link:
http://www.lockhaven.edu/~dsimanek/3d/stereo/3dgallery7.htm
7 years ago on Introduction
I myself look for them and turn them into puppet theater for kids.
It's a good project to do. The hard part is gutting them out.
You make it look so easy. Then again I'm not using a power tool.
After its gutted out I add fabric and some curtains
Then I put it on craigslist and cash in.
I have sold them for as much as $200 But maybe I should not tell people that. Lol
It started as something to do with my kids. I did not take any pictures of mine which came out a lot nicer then this one found on line.
It goes to show I'm not the only one doing them.
So keep in mind what you can do with the box after you gut it.
I was wondering about the liquid inside the lens.
Someone said it is deadly if mixed with water.
Is their any truth to this.
Thanks for your video. Live and learn
Reply 4 years ago
It's generally mineral oil, used for cooling.
4 years ago
Do all rear projection tv’s have a fresnel lens in them. Or do more recent ones utilise a different type of lens? If so, ideally how old a tv should still contain the fresnel lenses.
7 years ago on Introduction
7 years ago on Introduction
This is very useful. It doesn't look nearly as difficult as I thought. I wouldn't want to lug the whole TV home but it looks easy enough to remove the lens 'in place'. As long as you put things back, minus the lens, who would mind?
7 years ago on Introduction
I just salvaged one from out front Some guy came down our street and dumped it off in front of our house. I wonder if any use can be made with the three lenses?
8 years ago on Introduction
Would a 15-20 inch fresnel lens be effective for a cardboard solar oven? (painted black, insulated, etc.)
9 years ago on Introduction
I can't believe it... I had the chance to salvage a huge one, I mean like the double of the one of the video! If I only had known at the time... agh! Imagine how powerful it could have been...
9 years ago on Introduction
Okay, I've been waiting a while to find a projection TV and I finally found one in another state (we were giving two horses back and picking up mine) and someone had already taken the screens out of it, but luckily had left the one I need (I hope, it was kinda hard to test it when it was getting dark so I'm not 100% sure yet)
Anyways, we had to haul it back in the back of the horse trailer and it had fallen over (thought it was secure) onto fine pine shavings and a bit of horse poop (ew and will be washed) and I was wondering if scratches could hinder the screen very much. It was pitch black when we finally made it home and I couldn't see to check for scratches.
9 years ago on Introduction
I was watching someone making a cooker out of this; I had an idea of makeing a cement water storage & placing this on top for a solor water heater.
9 years ago on Introduction
Can you try to use the fresnel lens to make a DIY projecter that can be hooked to a portable dvd player?
11 years ago on Introduction
Thanks for the video! I just picked up a 62" DLP TV for free on craigslist last night for this reason and my power drill just finished charging! Time to get myself some quality free parts for my tesla turbine ORC project ;)
If you all want to know what I'm up to check it out at teslapower.wordpress.com
11 years ago on Introduction
Thanks for this, and very nice link. I demand your future laser instructable!
So what are you planning with the lens?
11 years ago on Introduction
I made a cooker out of one of these, I can turn a hot dog into a black lump in one min we checked the temp on mine at 3000 degrees on a bright day.
11 years ago on Introduction
Awwww, I just threw out a 50" DLP TV last month too!
11 years ago on Introduction
Our community has an electronic drop off where I usually use a pry bar or the lug nut wrench from my trunk to recover fresnel lenses. It´s quick and dirty, but the plastic housing usually gives way pretty quick.
11 years ago on Introduction
I really want to find one of these. I had a chance to get a broken rear projection tv a while ago but couldn't find the time to pick it up. Frustrating!