Random idea for multi-die LED flashlights

most commertial use 2 prisms to correct the beam

But what this does is expand the fast axis to match the slow axis, see image below, then you require a third lens in order to focus the light down.

The other option is to contract the slow axis so that it diverges less, like the fast axis, then use a second lens to focus the light to a point.

Even if you use the first method I’m pretty sure an acylindrical lens will perform better than the cylindrical one, for the same reason you can focus an LED with an aspheric lens and not a spherical one.

Also keep in mind that what we’re trying to do here is make the spot square and then focus it down to a point, not collimate it.

You don’t need to buy these kinds of lenses from the most expensive shop for lenses.

I would start by searching on Laserpointerforums.

There are 2 other LEDs that may be good when used that way:
Lumileds Luxeon CZ

  • CRI90 throw LED surrounded by Oslon Pures?

Lumileds Luxeon Neo

  • CRI70 only but 1.28 mm² package and may throw OK

If the dies don’t form a continuous light-emitting surface you will have dark rings in the beam. I learned this with my experiments with a 3x3 array of cree XD16 dies. The array formed a nearly continuous surface, but the slightly darker areas where the die corners meet caused a noticeable dark ring.

That was in full focus. I view this idea as best used in a zoomie. In full focus - use just one LED. Move the optics some and the dark rings are gone, you end up with smooth and bright flood or intermediate beam.

I’m not really sure…any chance that Samsung LH309A would be suitable?

Random idea:
Would XQ-E HI surrounded by 8 XD16 work well? Such array would be around 5x5 mm with plenty of flood. Would it throw better than 9 XD16? I don’t know, maybe.

They make color-mixing hybrid reflectors, mainly for things like RGBW or tunable-CCT emitters. So the emitting surface does not necessarily need to be on-center.

Blurring dies together for the purpose of mixing colours completely defeats the purpose of having a variable lit area die for maximum throw with a lens.

Also, it is not possible to have a parabola concentrate light from different sources into a single spot.

Or you take more lenses or more reflectors and put together

Regards Xandre

Tradeoffs, tradeoffs, tradeoffs everywhere. :slight_smile:

Mixed optics trade frontal area (and therefore throw) for versatility. But as multi-LED lights tend to have shallow heads, throw/volume can be quite good. I like that. :slight_smile:

Aspheric zoomie with Boost HX surrounded by Oslon Pures (or other CSP LEDs) with a Wavien collar is as throwy as it gets. And is an OK flooder as well. But not very efficient in a throw mode. And making it efficient flooder is not straightforward. And the tint shift from throw to flood is big. And cost is very big.
Such zoomie would offer way better combination of a flooder and a thrower in a single host than I’ve seen so far. And would be way way smaller than 2 specialized lights while being just as good at thow and 90% as good at flood. A dual-head light could compete better than a pair of individual ones - but still it would be significantly larger.

Any tool that’s adequate at two things is not great with either. They say here, Jack of all trades, master of none.

I kind of like the configuration of the X70. But if they could put a White Flat in the center with a larger reflector oreven fixed aspheric, then a perimeter ring of Nichia LEDs or whatever… Sort of like those prjector headlamps with the halo ring.

Or how about a 2-headed light? I always wanted to mod an S2 this way somehow, with a narrow spot TIR on one side and 3 up frosted wide spot TIR on the other. Somehow incorporate a gyroscope inside so the light knows when you spin it around to activate the correct light… Or two forward switched wired 3-way so when you flip around and turn on one side the other side turns off…

The point of this is to have a single optic that is used both for throw and flood.
Otherwise you’re wasting front area that could be used for more throw.
To have the most throw per frontal area it needs to be a single lens.

LOL did you read what I posted? A head on EACH END of the light. What frontal area do you waste when you use the rear of the light?

Oh in that case you waste internal space making the light longer, still a waste when you have a perfectly good optic at one end already.

What’s good for throw may no be necessarily good for flood, and vice versa. No matter what you do, there will always be compromise - that’s exactly what engineering is. The good thing with a double-ended light is that the flood end can have a rather short optic - or even none at all; it could even be a mule on the other side with a diffuser lens.

Congrats, you now understand why I came up with this idea.
So that you could have the option of max throw or max lumens without having to compromise with a large LED that gets a lot of lumens/efficiency but less throw, or a thrower LED that makes fewer lumens with low efficiency.