Flashlight concept #1 - Multi-emitter light

I don't know if using the red emitter in combination with the surrounding white emitters would result in a nice beam pattern. I would rather expect it to look weird. So, the red / deep red emitter is more likely to work separately as auxiliary illumination in lowlight scenarios (e.g. camping, preserving one's night vision, no attraction of insects, nightstand light, ...). Using the Osram White Flat 1mm² instead could be interesting to put out more throw as a centered hotspot in combination to the floody LH351D beam.

This looks like a great concept, I like it. I’d be more of a 4-LED 18650 kind of guy for EDC, but this seems like a good camping trip flashlight that can also serve as a lantern. 5700K while hiking for visibility, mixed tint while cooking food and 2700K when relaxing and reading a book. Just throw on a silicone diffuser and you’ve got yourself a lantern. Maybe a folding hook in the rear to be able to hang it in the tent or from a tree, with a magnet in the cap to keep the hook folded and still being able to stick it to metal surfaces.

I’ve been waiting for my IF25 from Aliexpress since 11/11, but I’m not sure when it will arrive, or how good it will be with the 70CRI 6500K SST-20s. Also waiting for my BLF LT1, but a flashlight like this could replace them both for my use.

So, I revised my original idea and tried to set up something new, something easy to operate...

(please excuse this rather simple design draft....just for illustration...)


Output: approx. 4.200lm white light with a mixed tint of 4.500K 90CRI and approx. 400lm deep red light (660nm), emitters to be driven efficiently - not pushed to their limits

Host: Proprietary, mid section maybe based upon Sofirn SD05 or IF25A, front section (head) new design with wider head diameter (40-42mm), tailcap + switch Sofirn SP70

Optic: LEDiL TAMPA NIS83-MX-7-W (wide beam, 35°, 38mm diameter)

Bezel: Stainless steel bezel

Emitter: 3x LH351D 4.000K 90CRI, 3x LH351D 5.000K 90CRI, 1x SST20-DR (660nm)

Driver: fully regulated boost driver (wishful thinking)

Power: 1x 21700 flat top

UI: magnetic rotation ring controls stepless brightness only (moonlight to turbo), tail switch controls modes (tap for mode selection between white and red light, fully press for ON/OFF)

I like this new idea :wink: :+1:
Seems a very well thought flashlight!
One question, though: the tailswitch would be a e-switch or a foward clicky switch?

I like it.

I like this, too. Nice design.

How about 9 LEDs? or have both a 7 and 9 LED variant.

Edit: 9 months ago I said 4 LEDs :open_mouth:

I like the thrower version.

Am I a minority here or what, but why would someone want a flashlight that is anything <5,000K. I know that a lower number K LED light will yield a higher CRI, but this is a flashlight after all and not photography lighting. If someone wants higher CRI then he/she might as well go back to using incandescent light bulbs. Newbie here, so please educate me.

I have my fire suit on, so go ahead: fire away.

Hi tammap!

It all comes to a matter of personal preference. For example, I use my warm white FW3A a lot at night when my eyes are alredy used to dim and warm light, and in that conditions warm white seems just white, and my neutral lights seem cool. It is just easier on my eyes, more comfortable.

Then again, I have a 2700K led lamp on my desk to study, just because I like it, and late at night cool lights don’t seem right to me. In addition, I think it is better if you have to sleep inmediately after stopping studying. In this conditions, the transition from warm lamp to warm flashlight is “seamless”.

Of course, If you like cooler neutral / cool whites then you don’t have to be educated, it is fine. I would try an inexpensive warm flashlight if I were you and had the chance, just to try it if you haven’t, but if you know it isn’t your cup of tea then again it is just fine, personal preference.

An e-switch would probably make this much more complicated to design (double-tube), so I would suggest using a mechanical (reverse/forward) clicky switch.

Not sure if there's a 9 emitter optic with less than 40mm. IMHO, going beyond 40mm will make this light too big and ugly using only one battery. Moreover, there's little benefit to expect with 2 more LEDs, making this light only "more floody" than it is already. :-)

I would also like the center LED to be something for long distance illumination. But I did not find any optic that has multiple beam angles, so something like Osram's White Flat will not work well here. In such a case, a classic multi-emitter reflector might be the better choice but then again the head diameter will become huge. UV LEDs will not work either as their wavelengths will be filtered out by most plastic lenses.

Concerning the tint: Many people here seem to favor a tint between 4.000K and 5.000K. The downside of HighCRI emitters is their worse efficiency but this could be solved by driving an array of six LEDs at reasonable currents, yielding in a beam that is both bright and pleasing for optimum color rendition.


I revised the OP with the latest draft and some spreadsheet about the specs. An integrated USB-C port might be a nice add-on, too?

Maybe add some knurling to the body? Preferably not the pineapple style though :confounded:

That’s what I was thinking! :wink:
As far as changing the type of light/led (white or red) that needs to be well thought so that we can always know what we will have when turning on the flashlight.

That is why I asked about the FC switch.
I am not sure if it would work but the way I imagined would be: from OFF, half press (or double half press) the tailswitch to change between red/white, and then a full click to really turn the flashlight ON with the already selected led ! The brightness level could also be defined more accurately before turning the flashlight ON.

That way there would be - in my perspective - less accidental changes between red/white, and a better definition of the level you want when turning the light ON.

Just a thought of course!

Very good toughts, MascaratumB! :THUMBS-UP:

I agree this light should turn on with a preset brightness (I suggest a low standard brightness) that can be turned up/down easily with the rotation ring. The FC switch would also be useful for momentary turbo (double/triple tap?) as a second preset brightness.

Meanwhile, I am somehow torn concerning the integrated USB-C port and the moveable ring being very close to the rotation ring. I am afraid the ring protecting the USB-C port could become loose by turning the rotation ring with thumb and index finger. But I do not see a good place to put the USB-C port elsewhere.

Thanks for the feedback Lux!!
Hum, I am not sure if I explained myself well, or - on the other hand - if I am fully realizing this concept, then!

When you mention a “preset bightness”, it got me confused.
I was imagining this light to be something like the Sunwayman V11R, in which you can rotate the ring to a certain brightness level (either the lowest, the brightest or somewhere in the middle) and then full click the reverse clicky switch to turn the light ON in that level.

The idea I presented for this project would be to have the forward clicky switch to:
a) alternate between red/white from OFF
b) have the momentary ON feature (in which we could also adjust the brightness by rotating the magnetic ring).
And then, from ON, the magnetic ring would change brightness both on white and red leds.

Of course, this solution would hinder the change between red and white while the flashlight continuously ON.

If this was the “plan”, a triple tap to Turbo would not be necessary because you could dial the ring up to max, and them turn the light ON /momentary ON (on both leds).

A double half click from OFF could be the “trigger” to change from white to red (assuming that white would be the default type of led, and red the secondary).

About the charging, could the tail be an option? I see many lights having charging in the back (both on the side of the tail or next to the tailswitch). Not sure if it is viable, though…

Again thanks for the ideas and feedback. And I am sorry if I am not understanding the project as I should :zipper_mouth_face:

Sorry for the confustion MascaratumB. Now I got you. :-)

Actually, I was totally "somewhere else" with my approach of a "preset brightness".... :FACEPALM: :)) I thought of something like this...
The rotation ring would have no markings to indicate what brightness level is currently set. So, I thought you wanted the light to start on some "default level" when pushing the button in order to see if red or white mode is being used. Nevermind, let's forget about this. :-D

Now, your approach sounds much more reasonable and sophisticated. But this would require some kind of scale engraved both into the host and the rotation ring to correlate with each other. Otherwise it would be impossible to preselect the brightness before one actually pushes the button. Would the picture below reflect what was on your mind?

Charging the light in the tail section is an intriguing idea but would that require changes on the tube design again?

Hey, no problem, I didn’t make myself completely clear :innocent:

Hum, well, I hope that “sofistication” in this case can help make things “better” instead of making them “impossible” :stuck_out_tongue: Ehehe

About the marks in the flashlight or the ring, I am not experienced with those. The magnetic ring flashlights I have are the old Jetbeam RRT01 and they don’t have any kind of mark/engraving . They only have a “dentent” mechanism that stops the light on min and max.

Other rotaries flashlights have marks and engravings (you can see in some of jon_sliders thread’s, as he loves rotary lights).
Those can be helpful when people start using the lights, but then you’ll know that you have a starting and an ending point.

Instead of engravings (that could imply more machines on the host), there can be aligned “grooves” (ex: I II III) both in the ring and the head structure to mark the start /middle/ end, if that helps. However, it will imply a precise assembling to put the grooves aligned :wink:

So, answering the question “Would the picture below reflect what was on your mind?” it can be that way (engravings) or it can be different (using sligtly machined grooves). In any case, I guess that this now reflects more the idea I was trying to expose :wink: Thanks for your work on it!

The Sofirn SD05 has those engravings: replacing it for grooves would be a nice thing (of course, adapting it to the total rotationof the ring).

I guess the tube wouldn’t need design changes, maybe only the tail, making it slightly longer, eventually, to accomodate the charging support. I was trying to search some examples : Wuben L60 and L50, Convoy BD03 (that is a diferent type of charging). How the charging in the tail interacts with the hardware in the head…that I don’t have a clue :smiley:

If I find other lights that have charging in the tail, I will indicate them, but right now I can’t find them :person_facepalming:

BTW, for the charging would magnetic charging be considered? Or would it be too much magnetic stuff in a light? :smiley:

Some brands that have it implemented: Olight, Imalent (some recent models), Skilhunt, Trustfire, Xtar. Not sure if it would be feasible/desirable for thus light, though.

Or maybe the C8F body tube and tail? Or am I missing something as to why SD05, IF25A and SP70 parts need to be cobbled together?

That would also be possible but as far as I have seen on BLF most people hate magnetic charging for it is known to be proprietary and needs a special cable (see Olight for example). I think the USB-C port could be placed somewhere near the rotation ring with a much smaller rubber boot in place.

I was more or less referring to the shape/design of these parts and to the reduction of development/material costs, not actually to the size of these parts. SP70's tail cap would not fit at all since it's a 26650-sized part. So, yes - C8F parts would be fine, too.

I Like the design. Maybe you can ask Fireflies to make it since the E07 is relatively similar.