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ArcticMyst Security by Avery

I screwed up big time!

Joined
Jun 29, 2008
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Alright, so I sat down today and decided I'd try to put together my very first blu-ray laser going by this tutorial here. The results were, while better than I expected, a clusterfuck.

Everything was going well until I got to the point where I needed to remove the PCB from my diode. I had to put the soldering iron on for what I suppose (keep in mind I have zilch real experience) is a relatively dangerous amount of time just to get the bloody thing off since I couldn't get a good grip on it with my pliers. I eventually managed to do it and had a bare diode pressed into my module that I presume was quite damaged (but at that point I had no way of knowing).

I then moved onto the driver (Lava microdrive). I trimmed it with a good pair of tin snips as advised so that it would fit the Aixiz module, then after some wrestling with the half-holes left managed to solder some wires to the contacts. I hooked up about 3.7V of NiMh to it, then tested the current: About .9 A. Yes, A. Not mA. Even while adjusting the pot, I found that there was little difference at all in the output current. An LED I hooked up to the driver while it was running at this current lit up properly without any issues, though its max current was supposedly 30 mA. What happened here? What did I do wrong?

Impatient, I then hooked this up to the laser diode since I had a spare one and switched it on. Now, at this point the diode is in the module and the optic screwed in in front (though without a spring, which I had the presence of mind to lose): My hour or so of fooling with these things has resulted in a very weak violet flashlight. There was no collimation at all. Also, the pattern of the "LED's" illumination was like a cat eye: Dim on two sides, a bright stripe in the middle of the circle.

So what's the point of me embarrassing myself so thoroughly like this? First, I want to warn the other kiddies out there who are also starting out to do more reading on how to properly put electronics together before trying to do projects like these. Second, I would like to know all of the things that I did wrong and what I should do next time.

Feedback would be much appreciated.
 





Joined
Jan 24, 2008
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Well, that doesn't sound very good. I don't know what happened with the lavadrive. But the diode sounds like it may have died from the heat you used with the solder or the possible .9A that it suddenly took. A lesson here is not to hook up your diode, possibly working or not, to a driver unless you have determined it's the current you want to use. BTW, how were you testing the current?
With taking the PCB's of the diode I find the second one closer to the diode is easier and safer to remove with some nippers.
 
Joined
Oct 26, 2007
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The output from these diodes have a wide pattern, not a circular one, so you might see a bright "stripe" in the middle when unfocused. Try screwing in your lens some more until you get a dot. Maybe it's still good.
 
Joined
Aug 21, 2008
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The colomating lens needs to be screwed in further then the module normally allows in order to get it to focus properly. So you need to carve/drill out the small hole opposite the lens on the black internal bit (it's plastic so it's easy) so that it can fit over the laser diode. Then remove the metal cap from the end to allow you to screw it in more then normal. This will allow you to focus it properly.
There are threads about showing how to do this, but i'm too lazy to find any ::)

Also putting 900mA through an LED would cause it to change colour to a dim red as it fried (regardelss of it's original colour) probably followed by alot of heat and maybe even smoke? As this didn't happen i'm guessing the actual output was far less then 900mA and maybe you measured it at the wrong place, which would also be why the pot didn't have any effect.

The diode may still be good but just under powered by that driver?
 
Joined
Jan 24, 2008
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Vardarac said:
There was no collimation at all. Also, the pattern of the "LED's" illumination was like a cat eye: Dim on two sides, a bright stripe in the middle of the circle.

Without pictures of the output it's gonna be hard to tell. This sounds more like a diode failure and gone into TEM0x mode than a collimation problem.
 

tomcat

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Joined
Sep 10, 2007
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right HOW and WHERE did you mesure the 0.9a... if you just "mesured" it thats wrong

1: go read electronics for dummies, http://knowfree.net/2007/02/19/electronics-for-dummies.kf

2: get a testload that mirrors your bluray diodes (someone fill this bit in please)

3: dont just "get impatient" that will ruin your life with lasers and all electronics really or even kill you if working with dangerous voltages,

4:???

5: profit

to get 900ma i guess you just put the probes on the output with nothing else there you need a testload to measure current try testing

900ma through a led would cause a local explosion and it would go BANG and pop flying plastic into your eyes so its deff not 900ma
 




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