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Water cooling my 400mw o-like green?

J

joeyss

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I was wondering since it's water proof could I just spray some ice cold water on the host and spread it around to help the laser cool down faster. Also could i just run it for more then a minute this way and is the cooling effect bad for the diode in anyway?
 





I was hoping for bit more than "spraying some water" on it when I read that title.
You disappoint me.:P
If it's waterproof, hose away, but it will obviously work only momentary.
 
Yeah I was hoping to see pics of some kind of awesome water cooler setup, but I start reading and "Can I just spray some water on it"
 
Yea can anyone confirm how bad this is for the diode and what if you used water at like 55 degrees? Is there way to do this without messing the diode up due to wide temperature fluctuations?
 
Dinas said:
I think it will be discarded soon, if you spray some water on it. The reason is not the water proof function that can not work, it just because the wide-ranging temperature that effects.
Click to expand...

wtf? :huh:

Anyway...

I wouldn't suggest water cooling in the method you describe. If you want to actively cool I'd suggest building a water or TEC cooled heatsink interface device instead of drenching the laser as I don't think this is what O-Like intended :D And this would only work if the host sinks and transfers the heat quickly enough and you can manage to sink and dissipate THAT heat.

Otherwise I would recommend that you stick with the duty cycle prescribed by O-like (100 on 60 off). Good luck either way.. and if you water cool that thing post some pics!
 
So if I do a 60 second on 100 off can this laser really last 5,000 hours? what if I use it every few minutes will that degrade the diode faster. I really just want it to last as long as possible while still being able to use it.
 
It says water proof which means you can submerge it right?

The diode won't be shocked because its in the middle of a heatsink. Think of the heatsink as a buffer, it won't allow "quick" fluctuations in temperature. I think you should be more then fine with submerging the laser in cold water. I would be more worried to the veracity of the water-proofing.

Good Luck
 
I've tested it under room temp water for a few minutes, but I got nervous cause I've seen a brightness spike so I took it it out. Could of been mode hopping.
 
I don't see any problems with cooling it as you describe. THe diode will handle the temp changes, however like you said, you will probably experience a bit of mode hopping as the diodes lasing wavelength varies around the absorption band.
 
new info: if you cool it too fast the laser chip will be destroyed. Only do that if you are aware of the risks, and do not use ice with water (5ºc lol).

for other readers: never cool your aixiz/o-like module with ICE or water or anything too much cold when the diode/host himself is too hot. YOU WILL destroy the cavity/facets/laser chip.
 
new info: if you cool it too fast the ... will be destroyed.
Click to expand...
Duh, more like old info.
Cooling is fine, shock-cooling (or heating for that matter) is severely disliked by most any material, and usually punished by literally cracking up.

What kind of diode did you kill now?
 
anselm said:
What kind of diode did you kill now?
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lol you are funny. not THAT funny, but somehow funny. ;)

I haven't killed any, just got a 5mW reddie and tried it. It works, if you froze it when it is hot it will be killed :P
 
Direct contact may result in thermal shock if the water temperature did not bring the laser diode to ambient during the start of its operation. A decent solution would be to use something like heatpipes, which then are subjected to water flow or CPU fluid coolers, that are in constant contact with coolant before, during, and after diode operation.
Impurities in the water may cause electrolytic corrosion on electrical contacts it may have the opportunity to contact. Water droplets that fall on the lens may cause divergence issues by changing the shape of the lens. Residual water on the laser casing may permeate into internal seals and risk fogging its internals the next time you turn it on.
Personally, I'd prefer the coolant [water or glycerol] to be closed loop rather than sprayed on, but thats me, ymmv ;)
 
Boo On the thread Title. Fired!!

Lame...Spray water....Hey anselm and benmwv We were Tricked!
 
joeyss said:
I was wondering since it's water proof could I just spray some ice cold water on the host and spread it around to help the laser cool down faster. Also could i just run it for more then a minute this way and is the cooling effect bad for the diode in anyway?
Click to expand...

As everyone is telling you, this is a bad idea. I too cooled a diode (cheapie red LOC) in the freezer and killed it instantly. Reason. As the diode cools down it becomes more efficient and therefore requires less current for the same given output. My freezer made my LOC go down to a chilly -25c! Also sudden drops in temperature will crack the laser cavity in the diode.

I suggest limiting your use to the recommended duty cycle.
 
Illuminum3415 said:
Direct contact may result in thermal shock if the water temperature did not bring the laser diode to ambient during the start of its operation. A decent solution would be to use something like heatpipes, which then are subjected to water flow or CPU fluid coolers, that are in constant contact with coolant before, during, and after diode operation.
Impurities in the water may cause electrolytic corrosion on electrical contacts it may have the opportunity to contact. Water droplets that fall on the lens may cause divergence issues by changing the shape of the lens. Residual water on the laser casing may permeate into internal seals and risk fogging its internals the next time you turn it on.
Personally, I'd prefer the coolant [water or glycerol] to be closed loop rather than sprayed on, but thats me, ymmv ;)
Click to expand...

Yes, this is a much better idea!
Good point!
 
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