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FrozenGate by Avery

I think I cracked my diode, help.

T

Tomtortoise

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Feb 23, 2013
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I got a PHR-803T diode from a sled but when I put everything together is is super dim

cnlNwH2.jpg

"120mw" 405nm on the right, 5mw 632 on the left


I believe I cracked it on extraction as there are a lot of abstract shapes around the beam. The other problem is it doesn't focus. I can get a good dot at one distance but if I move the module the dot gets huge. It is not the lens as I have tried 2 Axiz acrylic lenses that both focus the red laser

when I take the lens off the light looks like it should, ovalish in shape
 





What current are you running the 405 at and how do you know that its 120 mW? If you are running it at 120 mA you should expect 80 - 100 mW unless you have a particularly good diode. The lens you are using will affect power too. Also, don't forget 405 is not a very visible wavelength.

Admittedly compared to the 5 mW 635 it does look a little dim, but if you wanted to check, and don't have an LPM, focus the beam on some electrical tape and see if it can cut it. If you can, its probably working fine. :)

Remember to wear goggles when burning! :beer:

Edit: Just noticed you said you were using an acrylic lens. Acrylics aren't recommended for 405 as they tend to deteriorate over time due to the interaction of the plastic lens with near-UV light. You'd be better off with a 3 element glass lens. Also, are you sure that the lens is actually turning when you try to focus? If you are using a focus adapter, it could be loose and just spinning on the lens - this is a very common problem. ;)

Edit 2: One last thing I think I read sometime back that people had trouble focusing 405's with acrylic lenses, because the plastic lens housing is too short ie you cant screw it in far enough. It was either that, or the diode wasn't pressed far enough into the module. Either way try to get the lens closer to the diode and maybe try searching for "405" or "803T focusing problem"!
 
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I was looking at the wrong diode the 805T should be around 120, this one 80-100.
I have tried to burn tape but after a minute in the same spot it didn't leave the slightest hint of any damage.
 
Did you manage to get it focused though? You should be able to focus the 803T to a tiny dot. :beer:
 
Ok its possible that the diode is LEDed. Nothing much for it ,but to buy another sled and extract the diode. :(

Did you check that the diode window is clean and undamaged? Have a look with a magnifying glass, but make sure the laser is off and batteries removed!!

Did you take precautions against static and which are you using, a home made or bought driver? If home made, did you confirm that the current supplied is 120 mA or lower and with no ripple or spikes? (Only really an issue with buck, and boosts and less so with linears, but you should still have output caps.) Did you also make sure to short the output caps, before connecting the diode? Lastly did you see any bright flashes before this happened?:beer:
 
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So I looked at the diode and there is a little piece of green "glass like" material that rattles around. I'm just going to go with an 805T already pressed, definitely broke it with my less then professional extraction methods.
 
Don't give up on self extracting your diodes! Personally it is one of my favorite parts of the process....I don't trust myself to do it right on expensive diodes but even if all I find is a CD READER drive, which won't have anything but a weak IR diode, I will systematically tear it down and separate the parts. Its just fun....so don't give up!
 
I'm not giving up on all diodes on all sleds, just this one diode in this one sled. It's double heat sink is so weirdly shaped and hard to get off. It took a half hour of unsuccessful attempts before I took a drill bit and had to hammer it out, even that took a few minutes.
 
typically you should be able to take two pair of pliers and twist them in opposite directions and that will break the heat sink and free the diode.

here is and example fastforward to 3:05.
Disregard everything else!!!
 
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Before I took out the blu diode I practiced on the red/IR one first and that one had the brittle cast metal that breaks easily but the blu one had super smooth curved metal that made it super hard to get a grip with anything.
 
Buy a set of files at a hobby store or something and file down one side so that it is really thin. Then just use the pliers trick and the weakened metal should give easily. Just try not to get metal shavings on the diode window.
 
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