200 mw Red laser poblem

[Ricaboo]

Greetings fellow thread-goers! i' here to tell you about my very first laser, codenamed the HLP on dx and BG, as seen here

Not my image, but the same laser.
If you're still unsure, styropyro did a review of it here:

In recent days, the laser's beam has plummeted dramatically from it's awe inspiring 200 mw goodness to what i can appreciate to be as low as 2-3 mw.
Obviously, this has made the laser pretty much useless, but i want to know wether there is any way at all that this can be fixed.
I can confirm that this is NOT a battery issue, ive tried recharging my 3 sets of batteries, and even bought some disposables to see what the dang problem was- with all of them, the beam still stayed at the same level of 2 or 3 mw.
I've also opened up the laser and turned the little pot-screw in both directions, just hoping to see a power difference, but to no avail.
What do you think? Easy fix, or shold i just use it as a doorstop already? I can post more info if needed, please help!

 

[IsaacT]

Did you observe a duty cycle? It could be that the laser overheated and all but killed the diode...
Any drops or sharp impacts or damage? Things like that could reduce your laser to a piddly cat toy as well...
Other than that all I might guess is some sort of short or the diode simply died.

 

[matthewl]

sorry to tell u that it may be probably that ur diode is dead if the laser beam divergence was not changed. The shortcut of the circuit is not likely happen for u could see the light. in case of that u could check the voltage of ur diode. but dont expect too much.

 

[Ricaboo]

Well, i can say that as far as beam divergence is concerned, there seems no difference whatsoever. In fact, the puny little beam can still focus like normal too.
If you are asking what may have caused this, i think i seldom left the thing on for more than maybe a 1 minute duty cycle, but that's not it.
I have dropped it a few times, but most importantly, i was once tackled into water with the thing in my pocket, and stayed in the water for a good minute or two before realizing it - but this did not cause the damage, as when i took it out of the water and let it dry for a while, it still worked quite well, almost seemingly unhindered by the destructive event it had endured. It was reduced to a cat toy soon afterwards by an unknown reason.
If this is a diode problem as you fellas say, would it be a good idea to swap out the busted current diode for an off-the-shelf 200 mw red diode? And if it would, just how would i go about doing that? I can post pictures of the laser's internals if necessary. Please help!

 

[IsaacT]

Definitely post pics of the innards if you have them. Remember however that accidents can occur when doing any assembly or dissassembly and decide for yourself if it is worth it. If the laser is not functioning and you have tried everything then there isn't must risk.

 

[Ricaboo]

Alrighty then, i'll post a few pics of the innards as soon as i get home to my laptop, i'll keep you posted on the diodes i'm looking at as soon as i can, too.

 

[Ricaboo]

Right-o! At last i have finished the photo shoot. A few quick unscrew processes later yield this result here:
Front, or "pot" side is attachment no. 1.
Back side, or boring side is attachment no. 2.
A bad shot, attempting to show off the laser's pins, is attachment no. 3.
And a front shot, showing off the tip of the precious diode, is attachment no. 4.
An interesting thing is that it seems like all three pins available to the diode are attached to the driver - I'm no expert, but aren't those only supposed to be two attached?... moving on.
Aside from the pins, the only thing keeping the driver attached to the diode/heatsink/module housing is a bit of thermal paste. Also, the diode looks like it can be removed from it's housing thing fairly easily.
Also, this is the diode that i was thinking of using as a replacement:
Diode laser rosu 200mw capsula TO-18 5.6mm lungime de unda 658nm putere maxima 340mw
The site's in romanian - my first language, but the tech specs should be readable by any-language speaking person. (if you really need to, i can translate it for you guys...
How would you fellas go about taking the next few steps? I'm all ears... Awaiting your hopefully quick response...

 

[Ricaboo]

Aww, cr*p, I'm pretty sure i forgot to attach those... Well here they are, same order of pictures. Had to resize the darned things in Cs6...

 

[Ricaboo]

Bumping due to lack of responses.

 

[matthewl]

Well, i can say that as far as beam divergence is concerned, there seems no difference whatsoever. In fact, the puny little beam can still focus like normal too.
If you are asking what may have caused this, i think i seldom left the thing on for more than maybe a 1 minute duty cycle, but that's not it.
I have dropped it a few times, but most importantly, i was once tackled into water with the thing in my pocket, and stayed in the water for a good minute or two before realizing it - but this did not cause the damage, as when i took it out of the water and let it dry for a while, it still worked quite well, almost seemingly unhindered by the destructive event it had endured. It was reduced to a cat toy soon afterwards by an unknown reason.
If this is a diode problem as you fellas say, would it be a good idea to swap out the busted current diode for an off-the-shelf 200 mw red diode? And if it would, just how would i go about doing that? I can post pictures of the laser's internals if necessary. Please help!

I have to say ur diode is tenacious for being tortured so much. It is hard to make out how it died, for he cant speak any more. But u have to know this kind of diode is brittle even though it is more safe when is connected to the power circle.Maybe a finger spark or any others can kill it easily.I have seen the pics, and i think is a kind of press fit. So u scew the white part after solder off the PCB,the diode could be take off easily, I think.What is more, u had better check the PCB carefully to make sure it works well in case killing another. Just use the former one as a dummy load, it is easy.

 

[IsaacT]

Check the driver before tossing the diode....if for some reason the driver isn't working properly then it could be the culprit, and the laser could be fine.

 

[matthewl]

Check the driver before tossing the diode....if for some reason the driver isn't working properly then it could be the culprit, and the laser could be fine.

That kind of probability is scarcely if the voltage is proper.For that means the current is the operation current. It works in a normal state,but poor light emission, that the most probably reason is the diode dead. U could add my skype for more discuss. matthewliu5

 

[Ricaboo]

Well, I've just finished dissasembling the thing, and so far haven't encountered any problems: as far as the attached pictures go, picture number one shows the driver, still with some thermal paste stuck to it, and the other three depict the housing for the diode, which brings me to my next problem: I CAN NOT get the diode out of the housing, even if i press down on it with my whole weight. By this point, the diode was already broken but is now even more trashed, as you can quite clearly see in picture 2. I just wanna get the thing out, but it feels like its superglued to the heatsink assembly. Do i try to shimmy it out somehow or do i just drill straight through it at this point? (remember, the well-being of the diode is NOT a concern)

 

[IsaacT]

Well...flaminpyro actually has a tool that removes diodes without breaking them, but if you don't care about that you could definitely drill it out lol.

 

[Ricaboo]

Right, definetley gonna be doing that. I am honestly stunned by how well glued in the darn thing is. Aside from that, any off the shelf 200 mw red diode would do as a replacement, right? (for example the one i linked in a comment back thursday)

 

[IsaacT]

They should. Only problem would be if the laser diode that is in there is a different diameter. As long as they are the same package type it should work. And of course if you decide to use the same driver make sure and get the pos+ and neg- to the right input pins on the diode, since it is possible that the pinout is different. Not likely, but possible.