seeking advice on cooling 445nm 1watt

[bweasel78]

Hi i have a 800-1000mw 445nm OFL ttl laser module. also i have a couple of peltier heat pump plates and a copper heatsink off of a cpu from a desk top computer. would it be worth putting the peltier plate inbetween the laser module and the heatsink? would the extra cooling be beneficial? it is already in a square section finned alu heatsink so id be sitting the whole laser head 35x35x80mil on the cool side of the peltier plate then the hot side of the plate to the copper cpu heatsink... the size does not concern me basically will my laser benefit if it is ran cooler than it does now???

 

[Wytry]

It may increase lifetime a lot as it depends mostly on temperature. Usually lower temperature = higher efficiency too. However, don't run TEC at it's max current. You need to measure diode temperature and set peltier's current to keep it around 15-20 C. Lower temperature might be even better but it could cause water to condensate on optics.

 

[cilegray]

From the looks of it, your heatsink is allready overkill.

Mounting the TEC on there, running it @ full power with a good heatsink will only introduce condensation into the mix, besides... your laser doesn't need to run below freezing temp. Not something you want.

my .02

 

[Eudaimonium]

Your 1W blue laser produces maybe 3-4 Watts of heat MAX at the diode (I take it that the PSU is already properly cooled).

CPU heatsinks are designed to dissipate heat in excess of 100 Watts.

Adding Peltiers to the mix and you've got more trouble than the whole setup is worth. Even passive cooling works really well for 1W modules, active cooling is only neccesary if setup needs to work without duty cycle, like in projectors.

 

[bweasel78]

Thankyou all all these bits of advice and info are brilliant... overkill is something thats been part of my personality since birth I will leave the cooling as it is then..... i hadnt thought about condensation!! The reason for all the cooling was to have an unlimited duty cycle.... i have run it for two hours at 1.2amps and it didnt even get to body temp, so that will do me nicely I need to buy a IR thermometer so i can record the temps at set intervals, and have a look how its perfoming....
The comment about the psu heatsink, i assume your saying the psu heatsink is more than adequate on its own?

 

[Eudaimonium]

I don't know what your setup looks like, but if it's a commercial module, it's PSU should be properly cooled already, as well as the diode. No upgrade necessary.

Oh and, you said overkill?

Courtesy of Things.

 

[bweasel78]

when i bought it it was set at 600ma.... i now have it set at 1.2amps, hence my quest for extra cooling. The driver had no cooling at all and did get HOT, so i thought it would be good to cool it.... its done now 2 extra fans, cpu heatsink, a couple of tubes of heatsink plaster ... I like it, it runs forever without getting even slightly warm. And i predict it should last a lot longer like this.. im a comparative beginner and appreciate all tips and advice greatly.:thanks:

 

[jimdt7]

I have a small lab style heatsink for sale ! (check my signature)

Jim

 

[cheech226]

you could damn near run an argon with all that

 

[Benm]

Your 1W blue laser produces maybe 3-4 Watts of heat MAX at the diode (I take it that the PSU is already properly cooled).

CPU heatsinks are designed to dissipate heat in excess of 100 Watts.

Adding Peltiers to the mix and you've got more trouble than the whole setup is worth. Even passive cooling works really well for 1W modules, active cooling is only neccesary if setup needs to work without duty cycle, like in projectors.

Well, CPU's are built to run continously at temperatures of 70 celcius under load too

But a modern cpu cooler is plenty without TEC, usually no more than 1 K/W which means that it will heat up no more than 4 degrees above ambient at full power (provided you run the fan an position it as designed).

For the 445 lasers i would not add the tec: there is no benefit in running these diodes below room temperature, as the wavelength goes down with colder temperature, reducing visibility of the beam. With red diode lasers this is a different issue since lower wavelength is desirable for visibility on those.

 

[Deleted member 17304]

Wow, the only laser I've seen frozen before was WL's empty arctic host with a photoshopped beam in. What you have there... good god man all you need now is a vacuum seal around the glass so water can't get in. :crackup:

That said, if you can produce another one of those with an added vacuum port (for sealing) that will fit in a C-mount diode in it... let me know ok?

you could damn near run an argon with all that

Damn near is right, it's a shame such nice lasers are more efficient space heaters...

by the way to the OP, that's some crazy amount of heatsinking