Long shot: operating high power laser modules in vacuum

Do you have a question? Post it now! No Registration Necessary

Translate This Thread From English to

Threaded View
Dudes of all flavours;

I have an itch: I wish to run a 10W laser module in a vacuum chamber (UHV: 10^-6mbar or so).

Anyone got any direct experience of the 'fun' in keeping the diode cool?
And any tips on doing so?  
<heat pipes, lots of copper, lowered duty cycles etc.>

Cheers;

-James G.

Re: Long shot: operating high power laser modules in vacuum
On Thu, 28 Mar 2019 16:06:09 -0700, jrcgarry wrote:

Quoted text here. Click to load it
Water cooling loops will work, but that is pretty complicated.  In  
vacuum, metal surfaces that are pressed together conduct heat very poorly.
You need some sort of thermal conductor (either loaded silicone grease or  
gap-pads) to carry the heat across.  If your laser can be attached to the  
chamber by some structure, that can conduct the heat out.

Jon

Re: Long shot: operating high power laser modules in vacuum
Jon,

Aye, I've cooled lamps (tiddly 10Watt deuterium lamps, of all things) inside vacuum chambers with fluid lines on KF flanges in the past.

But the suggestion of mating that to the chamber wall's a good one - I suspect I'll have to remake the mount that the laser diode sits in.

<mind, I've yet to acquire the laser module so I suspect that there'll be some entertainment ahead to remove the diode, fabricate a new mount, and reassemble>

Thanks!

Re: Long shot: operating high power laser modules in vacuum
On 3/29/19 2:36 PM, Jon Elson wrote:
Quoted text here. Click to load it

Heat sinking to the wall is the way to go, for sure.  However, grease  
and polymers are verboten in UHV on account of outgassing.  You can't  
even use soft solder because it outgasses during bakeout.

I'd recommend using indium foil as a thermal interface between the  
module and the chamber wall.  If you compress it enough, it'll seal in  
the incidental gas it accumulates at ambient pressure pretty reliably.  
Otherwise it'll probably outgas like a screw with no vent hole.

Cheers

Phil Hobbs

--  
Dr Philip C D Hobbs
Principal Consultant
We've slightly trimmed the long signature. Click to see the full one.
Re: Long shot: operating high power laser modules in vacuum
Thanks Phil.

A solid recommendation - Indium foil is known to me - as is Grafoil.

Still prevaricating over the laser module choice.

Cheers.

-JG

Site Timeline