Deciding on building a 445nm Pen Host... help me decide battery & lens...

So I've decided to start building my AA 445 pen build and I need some "group think".

I want my 445 to be at least 1 watt output in a pen that is about 17mm in diameter. Super thin for a "AA" size pointer. I've purchased the rear clickies from DX and plan on making pen that screws apart in the middle. Threads will be .625" UNEF threads and the front portion of the pointer will have a complete copper heatsink carrier for the diode and flexdrive. Exterior will be bead blasted anodized aluminum. I can't decide on power source or lens.

a) Aixiz/Olike 405 glass lens or 405-G-1 single aspheric lens?
Jayrobs lens gives much better better but poorer divergence (about 3X more fast axis seen in pics). Wouldn't the aixiz give a better beam and power density at the dot and make for BETTER burning and beam pointing?

b) 14650 Li-ion or 2X Lithium AA power source?
The lighthound 14650 1100mA battery would only safely allow for about 1100mW output with 30min of runtime (assumes flexdrive 80% efficiency). It would also produce a pointer only about 130mm (~5 inches) in overall length. However 2X Lithium AA batteries would give over 2 hours of 1100mW runtime... or 1 hour of 1500mW runtime! But AA Lithiums cost $2.50/each and lengthen the pointer to about 165mm (6.5 inches).

c) Forget 445nm "AA" pointer and build a 12X 405nm "AA" pointer.
Microboost, 405-G-1 Lens, 14650 battery = 650mW singlemode 405nm beam with 1hr runtime.
Not such a bright beam... but low divergence & long distance burning power. MMMmmm.

Why not just use 2 14500 li-ions?

Bad voltage combination. 8.4v fully charged, 6v empty. That means I'd have to use a linear driver - inefficient and hot. I need a small drver easy to heatsink (flexdrive). Stacking 14500 cells in parallel is no good either. The clearance in the battery tube is only 14.8mm... not enough room for foil

forget the g-1, the only thing it is good for is up close burning, and showing it off on a LPM, if you have 1 g-1, thats all you need for all of your lasers, get an aixiz 445 lens for it and keep it on there unless you want to burn stuff up close alot quicker, or show it off on an LPM, thats all the g-1 is good for, the aixiz glass has a MUCH better beam/dot quality. and I would always take lithium rechargeables over standard cells

Forget the g-1

You should consider current delivery rather than capacity.
I'd say use the single Li-ion.

Those Energizer or Duracell 1.5v lithium cells may have far more capacity, but their internal resistance is greater. That means that the voltage will drop as you try and draw alot of current (~1 amp). It may not even work. They cannot supply the needed current, which trivializes their capacity. The capacity rating assumes their rated discharge currents. I can't generalize it and say ALL AA Lithium 1.5v batteries wont work, but I bet most will not be able to perform, let alone for 2 hours at a amp.

If I were to make a AA 445nm build, I'd run it at 900-1100mA and use this battery
AW IMR 14500 LiMN Rechargeable Lithium Battery
Buy two of them if you don't like the run time. But no other AA cell will perform as well when it comes to supplying the needed current.

AA lithiums, at least the energizer's data sheet are rated at 2A continuous discharge... and they should hold close to 1.4v @ 1A for over 1.5-2 hours. Is this not true?
http://data.energizer.com/PDFs/l91.pdf

I guess the aixiz lens is the one to have then. Perhaps I can build the tube long enough for 2X AA and then I can use IMR 14500, 14650, or AA lithium. The overall length of the pointer would still be shorter than 6.5"... which really in't bad considering my 2X AAA pointer is about 6.75".

Huh, I stand corrected. My experiences with them don't hold to what they claim on that data-sheet but I suppose they will work.

However, since they're only 1.5v the total will be 3v. I think the Flex drive need at least 2.6v or something like that. That gives you less of a "V-drop range" for your battery than if you used a 3.7v cell.

Either way rechargeable batteries will be cheaper in the long run. And it looks cooler IMO for such a powerful laser to come in such a small size. It fits more of the "pocket size" build theme.

-Tony

Good point. With the reccomendation of the IMR 14500 and the AW 14650 that gives me some options... perhaps I will size the pointer for the 14650 and use a spacer if I need the IMR. Flexdrive current draw for 1100mA to the diode should be 1.5A-2A from the battery. 1100mA should give me 1000mW after an aixiz/olike lens.

That little IMR would only last 20 mins... but it could do it. I guess it's not really a big deal because even the 14650 only lasts like 35 mins.

I wonder if the 405-G-1 with corrective optics would be an even better option. Dr. Lava was reporting ~1mrad with a good beam. I have been kicking this idea around for a compact lens setup... I was going to use it on my Kryton Groove when it arrives, but I guess I could use it for the pointer. http://laserpointerforums.com/f55/cylindrical-correction-optics-445-638-a-52925-4.html#post846692