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Don Foreman
 
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Luxeon LED's are available in three radiation patterns: Lambertian,
"batwing" which modified to throw more light sideways, and
"side-emitting" which clearly is intended for parabolic reflectors.

Oddly enough, the Lambertian pattern has seemed to work best in
reflectors in my experiments.

Focussing works fine with Luxeon emitters mounted on an aluminum stud.
I doubt if any of the mods do that, though. I think they all use the
Luxeon Star which doesn't stick very far into a reflector so there is
limited or no focus range.

I made one light using a Luxeon III on a threaded aluminum stud (for
focussing) in the 3" reflector from one of those $4.98 Everready
6-volt lanterns. It throws a beam every bit as collimated as the
unmodified lantern did, much more uniform (no dark spots or mottling)
and at least as bright. Lights up treetops half a block away with a
brilliant white spot.



On Tue, 17 Aug 2004 16:43:05 +0100, Tim Auton
tim.auton@uton.[groupSexWithoutTheY] wrote:

"John Manders" wrote:

[maglite mods]

I have seen conversions for the mini mag here in UK.
One question, does the variable focussing still work?


Incandescent bulbs produce (pretty much) isotropic radiation - the
same light in every direction. Maglite reflectors are designed for
this radiation pattern. Forward-emitting LEDs, which project their
beam in a fairly narrow angle anyway, mostly miss the reflector (how
much varies with the reflector and LED beam angle), so focussing
doesn't really work. I've seen mods with two back-to-back
side-emitting LEDs, which would presumably retain some focussing
ability, albeit with a slightly different pattern.

I'll stick with my Surefire E1e I think, but I'm going to get the LED
head when the next bulb goes. If you think maglite bulbs are expensive
then check out the Surefire ones! It's a silly flashlight really - if
I lived in outside the city I'd have something more sensible, but it's
so pretty and so bright I love it.

Flashlight freaks hang out he http://www.candlepowerforums.com/ and
there is loads of info available by searching the forums.


Tim