I hate tiny button cell lasers

I got two of these, and was quite disappointed by the batteries they use.
Each pointer is powered by three tiny button cells (no doubt meant for powering watches) that are completely inadequate at providing the constant 30ma or so the diode needs.
I got the lasers to play with my cat, so I need long battery life.
A solution had to be found.

I had a 720mah LiIon battery sitting around, from a Nokia phone that decided it had lived long enough. So I dismantled the casing, ripped the cell out and connected it to a clip-on connector.
I also dremeled off the outer casing of the pointer, which left me with the diode and the tiny board with the switch.
Some soldering, taping and gluing later, I have this:



The AA cell is for scale. The small pointer is the untouched one; on its right sits the other pointer's module and switch, hot-glued on top of the flat LiIon cell. It's connected to it with a clip-on connector, so that I can recharge the cell without having to redo the wiring every time.
The tiny button cell on the right is just there to show how the unmodified pointers are powered.

Ugly? Sure, but my cat doesn't care.

Why yes, my name is Dr. Frankenstein, why do you ask?

Next project: add a few tiny motors for windage and elevation, a control chip for programing patterns, and a motion sensor that turns on the laser when the cat walks into the room.

It is a proven, scientific fact; cats cannot see hot glue

Man, oh man, it did get run over (twice?) by the Ugly Bus but...I hate button cells too. Good job

Corona said:

It is a proven, scientific fact; cats cannot see hot glue

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YOU my friend are a loon ! Certifyably a loon. Nuff said. :twothumbs

Totally awesome. I love these cool, improvised frankenstein gadgets, it shows resourcefulness and originality.:rock::goodjob:

I'm almost scared to ask... how powerful is that... beast, for the cats sake? :candle:

my god I can't imagine going back to something rated 5mw. I was at a party with my family yesterday and one of the guys there "busted out" his 5mw pointer he got for fathers day. compared it to my DIY red at about 75mw ...sheeesh.

The same thing happend to me a couple days ago when a guy was giving a presentation and walked in with a 5mw greenie. Now, I'm used to green lasers that show the beam, even if it's only a little bit, in a somewhat dim room. This guy starts to point with this greenie and I'm wondering 'why can I still see the slide?'

I had been asked to stop using my AtlasNova (which is the only one I use in such public situations) which puts out about 30mW in a presentation once because no one could see the slide from how bright the laser was. Granted, I got no questions in the end because everyone was jaws to the ground with awe. So it worked to my benifit in the end

Cheers to more powerful lasers. :twothumbs:rock:
DDL

allthatwhichis said:

I'm almost scared to ask... how powerful is that... beast, for the cats sake?

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The laser's power has not increased.
It's a bit brighter, because the LiIon cell is unfazed by its 30ma current draw and doesn't slump. The three button cells, while in principle having more voltage, were so tortured by that current draw that their voltage slumped down horribly.
But the diode is the same one from the original pointer. I don't know its power in mW, but I do know I'd probably have trouble finding anything weaker.

The purpose of this mod is long battery life, not power. My cat is perfectly happy with the little red dot, even if it can't puncture plastic bags.

Now, when I have enough disposable income that I can get a 200mW DX green laser and power it with a big fat 18650 cell, then the situation will change...

I didn't know I could power the DX200mW with a 18650 cell... and given the power difference, I'm not very sure I want to risk it...

--DDL

Actually that was just a joke

I just had a look and that laser works from two 1.2v cells, so yeah, a LiIon would probably be a bad idea.
Two NiMH D cells, on the other hand...

hehe... I heard that Lithiums usually toast these diodes, and given how much it probably is overdriven to begin with, along with the lack of sufficient heat dissipation, I personally think it's just fine with some regular Alkies
Haven't tested it myself to see how the Lithiums change the diode condition. It probably has to do with the lower internal resistance, but I could be wrong.

--DDL

Or you could get it out of its casing, add some decent heatsinking and two beefy NiMH cells. That ought to be as death-ray-ish as it gets.

erm i hate to break it to you but i got one of those 20$ red laser/pen/highlighter things you get from the book store and when the 3 button cells went out on that I connected it up to 6 energizer rechargeable 2300mAh AA batteries and wow it made the out put like 3x brighter than before. Anyway just letting you know how far I have pushed mine and next i think i am going to go for 7

Mike

o ya the batteries are in series and not parallel erm I think. ya they go +{====]- +{====]- ......

Just out of curiosity, how long did your LASER last? Even assuming a voltage of 1.2 for the cells, that's (1.2 x 6 cells) 7.2V for a LASER diode designed for 4.5V.

It sounds spectacular -- did it last long? Blaze of glory?

-- Chuck Knight

well i just got back from colorado and i was up their a week and was using it almot non stop. and its just a bright. tho i think i need to rechage the battries now but ya its still working nicely to