spherical LED emmitters?

where can I find LEDS that emit light in a spherical pattern?

I've found the luxeon lambertian, and

http://www.superbrightleds.com/cgi-bin/store/commerce.cgi?product=LEDS&keywords=&cart_id=1404317.17672&next=50

a LED from suberbright LEDS, but that's all so far.

I think the best you may do is hemispherical.

Thurmond

Krenn said:

where can I find LEDS that emit light in a spherical pattern?

Click to expand...

What do you mean by spherical pattern? I don't think that's possible. I'm afraid my mental image of "spherical" may not be the same as yours. :thinking:

as far as I understand "spherical", You mean a round dot of light where You point the flashlight?
(probably wrong, as engl is not my primary language)
then just use an optic or a reflektor

or do You mean special lighting patterns?
like:
http://www.lumidrives.com/Products.aspx?name=OpticLenses
most still are round optics, only the elliptical and the flare lens differ

yellow said:

as far as I understand "spherical", You mean a round dot of light where You point the flashlight?

Click to expand...

That'd be circular.

I understand spherical as light radiating out in a sphere (as in omnidirectional). Under that light (pun intended), a star would be a spherical light source, but I don't think that's possible for a human-made light source.

greenLEd is correct. This is mainly for use in maglites for focusability, and as a candle, as the original lights were capable off.

I've mentioned two already that can do it: what else can?

So is this a test, or are you just weighing your options?

Have you used any of these and been disappointed?

A Lambertian emitter will ideally radiate a hemispherical pattern. In practice, I'm guessing that it's a few degrees less.

I guess if you put a couple of lambertian emitters back to back you'd be close to hemispherical... But you'd need a heatsink. Maybe this spherical array would be better with 4 lambertian emitters arrayed around a central sink? But that would not be a real sphere--just overlapping hemispheres to get you wide coverage. Plus, you would still need a "stem" protruding somewhere to carry power and heat. It doesn't sound very practical.

Has anyone built a (nominally) spherical emitter/array?

cratz2 said:

So is this a test, or are you just weighing your options?

Have you used any of these and been disappointed?

Click to expand...

just weighing my options. Different prices and brightness levels are appropiate for different lights, and I'm trying to figure out what's available, so I'll know what lights i want to retrofit.

within the usual Maglite upgrades, there are t-shaped "bulbs" that have 2 Leds pointing sideways (opposite sides of course).
Maybe thats what You want?

the Maxstar2N and the DB3W
http://www.terralux.biz/products/

The only reason I asked is it seems that usually owners of most side-emitting mods are quite dissapointed with the beam patterns.

I'm just trying to envision a role where a side-emitter will be a considerably better option than the high dome. I mean, if the high domes were that bad with reflectors, we probably wouldn't see the overwhelming majority of custom and semi-custom lights using high domes.

I think the idea of the side-emitters giving good focusability in focusing reflectors is about as ideal as using incandescents in the same reflectors... they basically work in the tightest 10% of the range and other than that, the beams are NOT pretty.

I have never used the new module with the two Jupiter modules facing opposite directions though.

A lamertian emitter works great in a maglite reflector - it just sits back further than the PR bulb. Since most of its light is thrown forward, this is desirable. A side-emitting luxeon also works great as a PR bulb drop-in - its radiation pattern is optimized to emit most of its light between ~70 & ~90 degrees off-center.

Side-emitters work great with shallow reflectors due to their tight radiation pattern. I'm guessing they don't work as well as lambertian emitters due to inefficiencies in the optic and because light from lamtertian emitters only needs to be "redicrected" once? You utilize the entire reflector with a lamertian source near the back. The most intense light in a lamertian/reflector arrangement is "spill," which helps with close-up usability and peripheral lighting at close/medium range.

The radiation pattern from a lambertian isn't uniformly hemispherical - they typically have maximum relative intensity at the beam center (or close to it) then gradually drop off to 0 at around 90 degrees; due to internal reflection, there may be bands of light past 90 dedrees.