200mw DX laser module power drop

[maxitoman007]

So, this weekend I decided after a failed attempt around a year ago to try once again to build a laser using a Dealextreme 200mw green laser module. This time I decided to use a nice C6 host from survival lasers. Anyways, after assembling the laser it worked Perfectly. The beam was visible in a well lit room and it burned various things with ease (after focusing). The module was powered by 1 18650 cell instead of the 2 AAA batteries that I have seen used (I've heard it shouldn't be a problem). Anyways, the next day I decided to test the laser with some of the different 18650s and when I put one of them in (after successfully trying another one) the laser power dropped significantly. The beam was no longer visible in light and the dot of the laser had also grown slightly (half an inch in diameter at 20 ish feet). So I thought it was the specific battery I tried but when I swapped back to previously working batteries the same thing occurred. I'm wondering if maybe I left the laser on for too long while swapping batteries and maybe it overheated? Or if there is another problem (maybe fixable?) that could explain these symptoms. I disassembled the laser and nothing appears to be different than before. I was really excited about my first successful laser build however it seems it has only lasted one night Any help is appreciated.

 

[HydroSean]

So, this weekend I decided after a failed attempt around a year ago to try once again to build a laser using a Dealextreme 200mw green laser module. This time I decided to use a nice C6 host from survival lasers. Anyways, after assembling the laser it worked Perfectly. The beam was visible in a well lit room and it burned various things with ease (after focusing). The module was powered by 1 18650 cell instead of the 2 AAA batteries that I have seen used (I've heard it shouldn't be a problem). Anyways, the next day I decided to test the laser with some of the different 18650s and when I put one of them in (after successfully trying another one) the laser power dropped significantly. The beam was no longer visible in light and the dot of the laser had also grown slightly (half an inch in diameter at 20 ish feet). So I thought it was the specific battery I tried but when I swapped back to previously working batteries the same thing occurred. I'm wondering if maybe I left the laser on for too long while swapping batteries and maybe it overheated? Or if there is another problem (maybe fixable?) that could explain these symptoms. I disassembled the laser and nothing appears to be different than before. I was really excited about my first successful laser build however it seems it has only lasted one night Any help is appreciated.

Which driver do you have and what is the output current? How long did you leave it on for?

 

[maxitoman007]

I'm sorry, I'm very new to this, how would one figure out which driver they have? Same thing goes for measuring output current. I had it running on and off for maybe 5 minutes while I was comparing batteries, not all at once. I have troubles believing it overheated due to the fact that I paid extra for a nice big copper heatsink. Thanks for the fast reply

 

[HydroSean]

I'm sorry, I'm very new to this, how would one figure out which driver they have? Same thing goes for measuring output current. I had it running on and off for maybe 5 minutes while I was comparing batteries, not all at once. I have troubles believing it overheated due to the fact that I paid extra for a nice big copper heatsink. Thanks for the fast reply

Theres two explainations I can think of:

-The wires connecting components may have become severed or partially connected. Check your wiring and make sure everything is solid connected with a full solid section of the wire at both ends. If you doubt your ability to diagnose the wires send some pics.

-5 minutes on is a long time for overdriven diodes. It probably overheated and destroyed the diode. I take it you bought this one right?
200mW 532nm Green Laser Module (3V 11.9mm) - Free Shipping - DealExtreme
If so read the comments, says it overheats after a few minutes of use. Most lasers that are pushed to beyond their specifications need a duty cycle of about 10 seconds on 45 seconds off.

 

[maxitoman007]

Yes, that's the one. If the diode was destroyed wouldn't it not turn on at all though? Like it still has a green dot maybe equivalent to a 5mw.

 

[HydroSean]

Yes, that's the one. If the diode was destroyed wouldn't it not turn on at all though? Like it still has a green dot maybe equivalent to a 5mw.

take it apart and see if any wires are half-connected or coming apart. send some pics of all the wires and the beamspot too maybe. hopefully diachi can shed some light on this because he is a master of those types of lasers (DPSS). might want to PM him and send him this thread.

 

[maxitoman007]

No wires look half connected or are coming apart. I tried to send pics but apparently that pictures from my iPhone aren't compatible. On thing I noticed while trying to take the pictures however was that the resistor (big blue thing?) on the module got quite hot, quite fast. Maybe this has something to do with the problem?

 

[diachi]

I'd put it down to using batteries that are potentially 4.2V with a module that requires only 3V. Sounds to me like you've either damaged the diode, or the crystal set - the latter sounds like the more likely explanation given the change in shape of the dot that you mentioned.

 

[maxitoman007]

Ya that's kind of what I was thinking thank for the reply