180º lens for 3watt or cree

I need a lens to protect a 3 watt luxeon or cree led that allows light to be cast in a full 180º +/- a little. It needs to be small <1" and easily attachable to an aluminum base. Any idea where to find one?

Thanks in advance.

Maybe try to find an acrylic dome and figure out a way to give if thread and just screw it onto the cap?

any idea of where i could find one with a flange?

If you don't need super high quality you could buy a little toy from those coin operated machines that they have in all the shopping malls around here. They usually have a little lip (<1mm) on the clear plastic dome that would allow a retaining ring to hold it down.

Greg

I sense a bikelight idea... that or a lantern? Whatcha cookin' Tim?

cave light. I want something that lights up my perif view. Something that lights in all directions as well as old carbide, but without the flame (can be dangerous when on rope or when uncareful in a tight crawl). All the electrical lights I've tried are too spotty. when I'm climbing up a rock I have to bend my whole head down to see foot placement instead of just my eyes. this throws off balance. I took a mini mag 3watt underground this weekend and put it in candle mode by taking the head off... perfect. I saw everything the way i wanted too. Now I'm going to build a helmet mount unit thats dimmable for small passages and battery life. 180º throw. and a whole lot lighter than chemical lights. I think this would complement my 200 lumen spot (big passages) and back-up tikkas perfectly. Now I just gotta figure out how. I'm new to electronics

Look for the thread about those 4xaa lanterns at Target. Someone in that thread came up witha great idea to use a clear 35mm file canister to help soften the streaky output from the stock reflector. For mine I just used the scotch tape trick but I'd guess some protection for your LED might be nice too.

People still use carbide lanterns?

benighted: Yea, they're still used. I saw several just this past weekend in use.

Film canisters and toy holders would never survive the abuse of smacking into rocks. I was hoping for a polycarb or glass lens, convex or fresnel as long as I can get the peripheral throw and still protect my emiter. Some way to mount it, like a flange, would be nice too.[size=-1][/size]

Carbide is quite dangerous...

But I think I have an idea...take a pyrex test tube or similar and just cut it down either using a flame or using some type of glass tube cutter and you can even cut stock head to allow gluing the window onto it for removal.

65535 said:

Carbide is quite dangerous...

But I think I have an idea...take a pyrex test tube or similar and just cut it down either using a flame or using some type of glass tube cutter and you can even cut stock head to allow gluing the window onto it for removal.

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Cut it with a tile saw (wet) fitted with a thin blade.

Thurmond

A bare Luxeon emitter will project light evenly distributed to 120 degrees. A cree is much narrower, and is not evenly distributed.

If you can get away with the wires exposed to atmosphere, just put a wire cage over it. That may be easier to find.

Bernie

Just a wild idea: How about a blob of clear epoxy mixed with aluminum powder right on top of the LED. It may not give you exactly the right dispersion pattern you want, but it will protect the LED.

EDIT: This place had various sizes of mineral glass: http://www.toolsgs.com/cart/browse.asp?subcat=259 but I don't think any of them are fresnel

Maybe just a blob of clear epoxy then invert so it forms a nice dome.

frenzee said:

Just a wild idea: How about a blob of clear epoxy mixed with aluminum powder right on top of the LED. It may not give you exactly the right dispersion pattern you want, but it will protect the LED.

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You'd be completely blocking the beam, GID materials are not translucent.

Tim, there are wide-angle acrylic optics available. The ones from Carclo come to mind first. I forget the exact specs right now, so you'll have to run a search on those.

Also, JonSidneyB (jsburlysflashlights.com) has some custom-made reflectors that fit the S7 Stenlight. If I were seriously into caving, I'd be looking into those.

Where at on your helmet will this be mounted? Top, front, above the bill? Are you wanting to illuminate the area in front of you?

I'm not sure I'm accurate on the details but I've been playing around with my Laserpod and those little decorative glass "beads" to try and get some better dispersion of the lights/laser. The glass beads I'm referring to are more like little "blobs" of glass that look like drops, round on top, flat on bottom.

I'll see how they disperse my L0P-SE in candle mode. If you could carve out the underside of one of them with say a Dremel or something you'd have a pretty small tough package. You'd then need to figure out the battery and wire thing.

You could cut and grind either glass or plastic and polishi it.

I will see if I can find the one I made ages ago, but you can try this. I was trying to do something similar but for 5 Lux-1 on a board and wanted it as low profile as possible but wanted a really wide light pattern.

I got some translucent plastic sheeting (I would estimate about 70% transmission). I cut it to the approximate shape I wanted. I glued a few nuts together and then put a ball bearing at the top to approximate the shape of a luxeon but just a bit bigger. I had to make 5 of these.

For my needs I glued these onto an aluminum plate at the positions of the luxeons on my board. I then placed the aluminum plate into stainless steel pot, sprayed on some PAM (seriously), placed the plastic on top, and put the lid on. I then "baked" the whole thing at 325F in the oven until done....sorry cooking humour. I think I may have used 325F though... it sounded right. Putting it into the pot keeps the direct radiant heat off the plastic and allows it to slowly deform. After about 15-20 minutes, the plastic had nicely "flowed" around the nuts. It did not hug the nuts as tightly as I wanted, but I did not play with it that much. More heat or more time may have worked better but this was good enough. You may not need the PAM, but I did not want the plastic to stick to the nuts.

What came out was very well diffused. and definately wider than a standard luxeon... though I am not sure how even out to 180 degrees it was.

semiman

humm, i am in need of some custom optics too. any good formulas to use. i am wanting a beam of 20degs x 90 degs off of a lux1. the smaller the profile the better. it is for the tail lights on my bike. i was thinking about just taking the oval optics from carlico and trying to round the wide end to spread it out further....any ideas?

hizzo3 said:

i was thinking about just taking the oval optics from carlico and trying to round the wide end to spread it out further....any ideas?

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My first impulse is to tell you it won't work. Optics are engineered for a specific beam pattern, and modifying them (especially if you mess with the sides or, depending on the optic, the top side too) may not yield good results.

My second impulse is to ask you to please try it and report in our discussion here. We're after wider-angle optics, and the widest available are around 50º.