DIY - Two-Colour Combiner Optic Project - for the C2

I haven't seen much in the way of true two-colour combined portables. I had always thought that the big stumbling block would be accomplishing adjustable dichro mounts inside a portable form factor.

Then I saw Reginak's disassembly of the CNI units, and it appear that they don't use adjustable dichros at all.
http://laserpointerforums.com/f51/help-me-cni-rb-640-445nm-640nm-67834.html#post978952

I got thinking about hosts that would potentially be able to hold a similar DIY combiner module. The easiest and most obvious would be the C2:
Ultrafire C2 DIY Cree LED Flashlight Shell/Casing Complete Set with Driver Pill (1*18650/2*CR123A) - Free Shipping - DealExtreme

This gave me a rough sense of dimensions to design the module around. I'll order a C2 and get precise dimensions if there's interest in this project. But essentially, I went forward with the estimate of an overall 36mm diameter, and a height of 30mm (this may actually be pushing it on the height figure available for a module inside that host).

So I came up with this concept:


Essentially, each module tunnel is hollowed out to an inner diameter of 12mm all the way through. Then each module tunnel is hollowed out to a 12.4mm diameter from each end, almost half the way through. However, a 1mm wide (and 0.4mm high) "pivot ridge" is left off-center in the middle of the tunnel. The Aixiz module will straddle this ridge, with four set screws, two on either side, providing for up/down and left/right aiming of the Aixiz modules.

You would roughly equalize all eight (four per module) set screws, and then epoxy your diodes in place with the beams activated and hold the dichros steady while the epoxy dried (5 minute epoxy, with minimal shrinkage/expansion after setting would be crucial). Then the set screws could be used for future fine adjustment if it became necessary.

One drawback I can see is that the "pivot ridge" approach implies poor heatsinking contact with the tunnel walls. Even with heatsink compound filling the gaps between the modules and the tunnel walls, you wouldn't want to be running 445s at high power.

The other drawback would be price. I think with 10 or so people in on this, I could probably get them made and shipped out to everyone for $40 or $45 (you'd have to find your own dichro / mirror). Shot in the dark. I never would have thought an approach without the ability to micro adjust the dichros would work - but apparently it does for CNI.

This is very interesting to me!

When I saw that picture of the insides It got me thinking as well

Your estimated price is more than reasonable in my opinion. Your design looks pretty good! Nice work.

I'm sure there would be some way of making a pivoting, tilting dicro mount is basically a small rotating disk which can be tilted via set screws.

Neat idea by the way!

Definitely interested in buying one when you make them! Ive wanted to attempt a 2 color handheld for a while. Great concept!

Alright - I'll get my butt in gear and order a C2.

While I do that - you guys could help me by keeping an eye open for another easily accessible (read: fairly inexpensive <$30 ish, and in stock) host that might have more cylindrical area for this module to fit in. It's not so much diameter now, but rather height (of the module, or height of the heatsink if this was a traditional build).

You've seen this right? SacredFire NF-009 Cree Q2-WC 160-Lumen LED Flashlight (2*18650/4*CR123A) - Free Shipping - DealExtreme


Edit: I don't know why CNI have chosen a dichro for reflecting the red. Surely it would be cheaper to just use a first surface mirror.

Isn't possible to use 3.8mm diode for that build ? 3.8mm red and blue LD are available. The diameter of the host will be significantly smaller. It will be hard to find smaller module to fit the 3.8mm diode.
The Opnext blue LD has a nice round dot which will be a perfect match for the red dot.

LaZeRz said:

You've seen this right? SacredFire NF-009 Cree Q2-WC 160-Lumen LED Flashlight (2*18650/4*CR123A) - Free Shipping - DealExtreme

Click to expand...

I think that host has the same size head as the C2, no?

Blord said:

Isn't possible to use 3.8mm diode for that build ? 3.8mm red and blue LD are available. The diameter of the host will be significantly smaller. It will be hard to find smaller module to fit the 3.8mm diode.
The Opnext blue LD has a nice round dot which will be a perfect match for the red dot.

Click to expand...

There are a few reasons not to go that route:

1) This isn't a press-fit combiner, and really can't be with this approach. We're utilizing the independent-module nature of this setup for the set-screw aiming.
2) So 3.8mm would save a bit of size, but only if the modules themselves are smaller. So far, 3.8mm modules have been Aixiz clones (which would still work in this design anyway)
3) Using 3.8mm modules that were smaller, while saving overall size would limit flexibility, but for diode selection, and for lens selection (assuming non M9x0.5).

That's a nice looking design, but as you've stated thermal dissipation is going to be an issue with the limited contact between the structure and modules. If your only planning on very short duty cycles you'll probably be fine, however you will likely need to re-adjust the alignment from time to time due to creep (thermal expansion) unless your only operating it at the same temp you initially aligned it at, maybe + or - a few degrees. All in all I think it should work fine though. A different approach from what I've been developing but interesting none the less. Good luck!

Made a few modifications. Added some 2mm high steps, at roughly 1.3mm intervals, to aid in the positioning of dichros/mirrors at 45 degree angles to the beam, and at 90 degrees vertical. It should allow for flexible dichro/mirror thickness combinations.

Beautiful. =)
You're going to make a 2 color build very easy comparatively. Haha

sassafrass686 said:

Beautiful. =)
You're going to make a 2 color build very easy comparatively. Haha

Click to expand...

Easy once I find a spare $780 sitting around to actually fund this little project

Well, I need to order a C2 from DX first - I'll go do that now. I'd be thinking XMas time before I place the order, then mid January to actually get these things out there FS.

Nop, the head on c2's is 40mm compared to 56mm on the NF009

this will be magical if you succeed.

Go hard son!

We will have to resort to aluminum/copper modules with a crapload of thermal paste around them for builds like these We need all the heat dissipation we can get.

Btw, Do you have any idea's for a retaining "plate" that can be placed between the heatsink and host walls that would would be either polished aluminum or just a piece of black plastic with an aperature hole? That would ovbiously ensure dust protection and better looks. You probably could also glue a high transmitting lens which would make the whole thing water and dust proof (If the rest of your host is waterproof)

I guess my final reccomendation would be using a host like the nf-009 or similar which allows for more headroom which would also let you move the two holes a bit to the side so the output isn't exiting the host completely to one side.

I can't wait to see future prototypes! :beer:

RHD, I like how you started off here by copying the Chinese. (Vs how it usually goes )

(You've enhanced the design since but...) -- turnabout is *such* fair play in this situation