Random idea for multi-die LED flashlights

9 XP sized leds….not with a reflecotor but with aspheric? Costly, but otherwise sounds good.

Yeah, something like that :slight_smile:
Switching between 1 and 9 dies will go between throw and output, and focusing with the lens will switch between spill or tight beam.

This way you can have maximum throw, medium throw with large high lumen spot, or high lumen flood.

It should be even possible to mix different LEDs.
CSLPM1.TG in the middle, LH351D on the rim?
Or, for those who can’t stand cool white, XP-L + LH351D.

How would it work with a wide-open collar?

It is still a prototype but Osram is working on a 1x1 mm high power led that could be used for this, it just needs a 9-up MCPCB.

Made me also think of this: Osram is working on a 1000 ‘pixel’ led that can be individually controlled. It will however not have the lumen density to make it throw very well.

Had the exactly same idea 1.5~2 years ago, but problem is "four-nut" hole with 9x,25x etc. discrete LED arrays. To eliminate hole(s) op reflector must be used, which reduces throw significantly.

With LED like 9-die XHP-35 HI this would work with SMO reflector.

Yes, it definitely needs to be a single LED, not 9 or more LEDs soldered beside eachother.
9 die XHP35 is a perfect example, since the current one is 4 and has no visible cross.
The main feature would be turning on the center die individually.

We will likely never see an LED like this produced, but I thought it would be good to write the idea down somewhere so it’s on record :slight_smile:

Interesting idea.

And the LEDs don’t have to all be the same. Put a very high intensity LED in the center for max throw. Surround it with bigger-die, lower-intensity emitters that can be activated for max lumens and flood.

Could make a great searchlight. I don’t think this would be practical for an EDC though unless you’re just making a mule with no reflector.

If EDC flashlights can fit an XHP70.2, then there wouldn’t be any problem with a 9 die XHP35 in the same light size :slight_smile:

Bare tiny chips are widely used in automotive industry last 5 or 6 years. Just few problems:

- Osram wont sell them if you are not working for BMW

  • You need a small factory to mount this chips on your own substrate
    And yes you wont find many information about this products on osram website.

Some further thoughts on doing it with aspheric and collar….
Combining multi-led idea with collared zoomie enables making a light of the size of Brinyte B158 which delivers 500+ kcd throw and 5+ klm flood. The former sustained, the latter being turbo.

But aside from the regular challenges with collared light (patents….), there are also new ones.

If we want wide beam, we need wide collar opening. Also, collar won’t focus on the flood leds, reflecting their light partially on other LEDs (which is good as it enables recycling) and partially on the PCB.

If we want wide opening there are several options:

  • make a wide-open collar with mounting fixed against the LED
    • in throw mode, lots of light escapes the collar reducing throw
  • make a collar with large diameter, moving together with the lens
    • the light loss is at high angles, this is less of a problem than with fixed collar
    • collar comes out of focus quickly, making partially focused beam much less useful
    • complicates head construction
  • combine fixed and moving partial-collars
    • complex, costly
    • restricts zooming movement - they’ll hit each other quite early
    • less of a problem with stronger lenses
  • do Fresnel style collar
    • complex
    • is it reasonably manufacturable?
    • light collection will be good, but precision will suffer, reducing efficiency too

If we want to reduce collar-induced losses, white PCB comes immediately to mind.
But that produces ringy throw.

Kiriba_ru had the same thought as me. Osram offer an automotive LED which basically has “pixels”. If you use an aspheric lens you basically have a projector (finally making the bat logo possible whithout a lot of effort on the optics front).

Oslon Boost HX surrounded by Oslon Pures…dream team?

Another dream…might be hard to implement and may not even work well, but maybe…
Put Boost HX surrounded by Pures in a host. Implement zooming by varying intensities of the central and surrounding LED. Full throw has just the central LED with high intensity but few lm. In flood mode you drive all the LEDs at not-too-high current leading to high output with high efficacy. There are intermediate modes as well, they probably feature a bright hotspot and a wider secondary beam.
Now…put that in a TIR based zoomie. Synchronize the zoom head movement with LED zoom, so a single control turns the light from a very narrow high-intensity thrower to a high-output flooder.

Wouldn’t work very well because the HX has a big border.
You need LEDs that go all the way to the edge so that when they are all on it looks like one, otherwise you will end up with a weird looking hotspot.

Hotspot-donut-hotring? Some blending would take care of that. Would compromise throw, but not much.

Well, if you use only the center LED for most modes, then turn on the outside emitters when you get into full flood mode, it might not be so bad. Another option is to use a multi-emitter optic, like the 6-up and 7-up optics that led4power is selling. But, it might be hard to implement a smooth zooming function with those. I don’t know if “zooming” TIR optics are much different from “normal” single-focus TIR optics or not.

The main benefit of this idea would be the whole front area is used for a single optic, resulting in the maximum throw when a single LED is on.
Multi-emitter flashlights are good for lots of lumens or high efficiency (driving all the LED on low) but not good for throw because each LED get’s it’s own small optic.

Honestly in the near future a single LED will be able to have extremely high lumens and great throw at the same time which would make this entire idea unnecessary and overcomplicated :stuck_out_tongue:

“Honestly in the near future a single LED……”

Sh*t. The way technology is going ALL my GD lights I’ve spent all this munny on since Mother Teresa was in short pants are gonna become essentially equivalent to empty GD HOSTS.

:laughing: :person_facepalming:

I’ve been thinking about it some more. I would do it in a simpler way….never have both LED groups on at the same time. Nearly focused=central LED, most other modes=peripherial ones. At the time of the switch the user would notice tint shifting and beam widening. It would make it impossible to have some beam widths. But it would avoid the tint shift caused by having the central LED with a different tint (even if the same CCT). And related CRI loss. And would just be simpler.

No, I really don’t think there would be a donut hole problem as long as the switch point was chosen properly.

As to single emitter being able to do it all…in several years LEPs may be able to do that. But not sooner. And only maybe. Efficacy is simply not there to challenge LEDs in high-output flooders. Like the one described here.

It would actually be possible to use Soraa LEP surrounded by LEDs just like we discuss here. Though its footprint is quite large.

With an LEP it might be possible to physically change the size of the dot being projected on the phosphor, by changing the focus of the laser collimator, allowing for laser power to be increased.
Basically the “wider beam, more lumens, better flood” theory without using multiple LEDs.
Only problem is that even a single 6W laser diode is quite inefficient and gets hot without appropriate cooling, so it would no longer be EDC size.