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ArcticMyst Security by Avery

Planning my first build/mod

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Nov 5, 2010
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So I've been a member for just a couple days now and I'm overwhelmed with all the info that is available on these boards. I love it. I've read up on a few guides on how a laser works and I have a pretty good idea of what I want to do. First I got to order a rechargeable 18650 2900mah battery. I don't believe mine is rechargeable ( because I haven't gotten it yet with my laser purchase). Next, I bought a 500mw blue laser and I plan to up the output to 1w which means I need to take apart my laser and make sure the driver is up to the challenge, as well as the diode. I haven't soldered anything for over a year now. I'm sure I'm rusty. I've also wondered if it's possible to swap the blue diode out for a green one to make a tight beemed burning laser. The objective on the laser I bought is adjustable, so I should be able to focus it just fine. Anyone have experience doing what I want to do here? I'm fairly versed in electronics and used to make make my own pcb boards to modify my parallel port signals to do things like turn my house lights on/off back when parallel ports were used on computers. Or, anyone have advice for me in this endeavor?
 





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Since you're experienced in electronics, it makes the explaning job easy.

Firstly, there are no green diodes. There are only green modules, and no you cannot replace it just like that.

Second, there are two types of drivers commonly used in handhelds:
Linear regulators, alikes of LM317 and so, and
Boost drivers, also known as DC/DC Converters.

Firstly, your 18650 cell is most likely rechargeable since I am yet to see a non-rechargeable 18650. If it says "Li-ion" on it , it's rechargeable.

You need a charger too, I reccomend this:
DealExtreme: $8.76 TrustFire TR-001 Multi-Purpose Lithium Battery Charger

Next, the 445nm diodes work at aproximately 4.5 Volts, more or less, depending on each unit.
As your lithium ion cell is only 4.2 V max sufrace charge, it means you need a DC/DC converter. Most popular ones here are circuits designed by DrLava, he makes two types of drivers:
Flexdrives - buck/boost ones and
MicroBoost - boost only

Pick them up here:
http://hacylon.case.edu/ebay/laser_diode/Micro_BoostDrive.php

Or PM Drlava on this forum directly.

If these options are too expensive for you, there is another solution.
When building your own laser, you can use a linear regulator like LM1117 (my reccomendation, cheap as dirt these days, better than 317), and use two CR123 sized lithium ion batteries known as "16340", two of those fit in place of one 18650 nicely.
Although rare, but much better solution are batteries known as 18350, much better battery life and current draw possibility.

I think I saw some 18350 on Kaidomain, but I'm not sure.

In any case, if you are building your own laser, you got all the choices you need.
If you are buying one, you do not have choices and opening the laser will result in voiding warranty of any kind.

It's up to you.

If you need any further help, please feel free to PM me and I'll explain everything you want to know.

EDIT- Addendum:
I forgot to mention that diodes require constant current source to operate, NOT constant voltage, otherwise they will work very short time, if any - as you can imagine.

Also, please remember! Patience is the key to success in this hobby!
Time.jpg

Laser diodes that I dented. :(
 
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Thanks, I appreciate the help. I've got CR123 batts around here somewhere, I'll go that route with the LM1117 since it's gonna be my first build. Why screw something up that's expensive you know?
 
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Thanks, I appreciate the help. I've got CR123 batts around here somewhere, I'll go that route with the LM1117 since it's gonna be my first build. Why screw something up that's expensive you know?
Good thinking.

Also, make sure you heatsink your LM1117, it'll dissipate a lot of heat at currents near 1A or so, which you should be aiming for.

If it's a portable handheld build, you'll need to get creative with heatsinking the driver. You could fit a TO220 one inside 12mm hole meant for driver inside your host's heatsink, or the place where Aixiz's back end is going to be.

All you would need is LM1117, and one resistor. Forget capacitor, trimmers, reverse polarity diodes. They just complicate matters and give you a lot of room for error.
 




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