685nm Laser Pen Build (Picture Heavy)

The purpose of this thread will be to show how I made this, and to hopefully give someone some ideas,
and of course in the replies I can get some good ideas also


It started when I read this thread and decided I wanted to use the diode in a laser pen.
I had previously built a 635nm 5mW laser pen, so I had some experience with building a laser in a pen host.



Parts:
Host*: Laser pen (LINK)
Diode: 685nm 35mW (LINK)
Driver: AMS1117 ADJ SOT-223. (LINK) Set to 56mA with 22 ohm resistor
Axiz module with included acrylic lens




The building process:


Starting out with the diodes.


THE diode.




Initial testing showed 2.33V @ 56.5mA. 34mW output. Polarity is the same as in Lightning Stalkers' thread that I linked at the top.

Parts. Although I didn't use the spring or bare switch.


Building the driver, took a little finagling to complete.



Driver soldered to the diode.
Since there is no case pin I had a difficult time trying to figure how to make the negative case connection to the diode. So in the end I bent the negative pin over and soldered a blob of solder on the end, so that when the back cover was on the module the blob would hopefully wedge against the module to make an OK connection.






Now, for the switch I used the original PCB from the laser with the switch and just cut it in half at the line.


Added copious amounts of hot glue to reinforce it.
And slid it in. Since I used electrical tape to make the module fit in snugly I stuck a small springy piece of metal in between the exposed part of the Axiz module and the inside of the host.



With that done, there wasn't much more to do but do a final focusing adjustment, put the cap on and test it out

Final Specs:
Power: 19mW with one Li-ion. 24mW with two Li-ion batteries.
Divergence: ? haven't tested yet.
Total price: a little under $9


And the mandatory beam shot. I had a hard time trying to get good ones with a bad "camera" and because of the low power and visibility.




Thanks for looking.
-Mattronium



*
P.S. * about the host. It proved challenging to remove the original occupants of the host (pressed in aluminum heatsink, but I did find out that WD-40 helps a lot.
Even then it still wasn't easy.

Very nice. Like your mini driver too! :beer: and +1

Pretty cool, did the pen "cap" attach fine to the aixis module?

This is the kind of stuff Pman loves. Inexpensive do it yourself figure it out make it happen. Especially like the bent pin to complete the negative and supporting the back side of the switch.
+REP.

Grainde is about to hit 2000th post

Nice I still need to get some of those diodes. I have one black pen host left, I think one of those diodes will find a home in it. I love a nice laser pen, though it seems I am one of few.

I love the build, mostly because I am impressed with the small form factor. I have an incredibly hard time working on the small scale and am always impressed with someone who can,and make it look good too!
+1rep

Atomicrox said:

Pretty cool, did the pen "cap" attach fine to the aixis module?

Click to expand...

The pen "cap" is not attached to the Aixiz module, the Aixiz module is recessed far enough that the cap can fit in/on normally.

Thanks everyone for the comments.