semi-ghetto peltier-cooled handheld lab device

[Zom-B]

Here's my latest build, my first 445nm.

It starts out with the idea of peltier-cooling it because I heard it becomes really hot at full power. I looked around my workshop for something that could hold an Aixiz to a peltier and found a plate with a convenient looking springly clip, and I found a box that's just the right size... for it to put on top. the metal plate is too big to fit it inside, and as later turns out, stuff wouldn't have fit even if I cut it to size.

I also found a heatsink from an old pentium II, which fits precisely when I cut the sides off:



I cut some holes in the heat sink to feed the peltier wires:



Peltier driver, LM317, now still set way too low, screwed on ample amounts of thermal grease:



Cooling fan, big holes for air, etc:



Yep, it freezes:



BlitzBuck drive @ 1.7A and somewhat cooled using a mounting board and more thermal grease:



Laser in place, also with thermal grease. I had a hard time figuring out where to drill the hole, so I powered the laser at a very low current with the lens focused to a tiny spot, then measured the distances. After the first hole with a 1mm drill, I was still off by 1.5mm, which I fixed by drilling three holes in a line (middle one at right location), then expanding it with a 3mm drill before going on:



Cheap stuff sometimes breaks:



Well, on with the real stuff then:



First thermal test, 30 seconds:



Using a very old PIC thermometer with One-Wire® sensors:



It gets really hot, so I screw up the peltier from 6.6W to 12.5W (which is 2.5A, even though the LM317 max is 1.5A). After this, it still climibs to 50°C (122°F) after 60 seconds.

[no pic]

A battery pack, and we're done:





Beamshots!!






The laser doesn't focus well with the supplied multi-element AR445/405 glass lens, as can be seen here:

Too far in:

\
Too far out:

Spot after 16 feet, is 3/4 inch, indicating 3.9mrad divergence:

I know it isn't backwards, because it looks even worse and the lens almost falls out:

I contacted clif and he said he didn't have any more lenses in stock and suggested that I perhaps disassemble the lens to see if anything is out of place. I don't think that's the case since it's perfectly rotationally symmetric. I'm still discussing it with him before I take any action.

 

[sinner]

Re: semi-ghetto peltier-cooled handheld lab decive

Nice ghetto handheld-labby hybrid concept, I like it..

 

[Zom-B]

Re: semi-ghetto peltier-cooled handheld lab decive

I might be wrong, but I think my switch can't handle 4A, lol.

 

[Zom-B]

Re: semi-ghetto peltier-cooled handheld lab decive

This ought to do it:

It was 3.2A btw.

 

[CDBEAM777]

HH can be in ANY shape !!! Nice combination.

Might I suggest...Go to O-Like for a lens which...as far as I am concerned.....colliminates the 445 the tighest.....Look for;

05/450nm laser coated collimation lens /glass/three layer

For $ 7.95.....does a great job.....the next step is the use of
pair of anamorphic prisms..... see the " Tridentis" post.

The PO will drop unless you can maintain about a 25C core temp.
Difficult to do with a TE.....But I believe possible.

I have no expeience with the driver you are using....but I believe THAT may be what is generating excess heat......try an X-Driver from Lazeerer....very efficient....

And....if you have funds enough....switch over to an 9MM 445 LD....with an 2.2A X-drive attached.....it is only money !! !hahaha.....

Do check out that lens though.....for 8 bucks....you cannot go wrong !!!

CDBEAM=======>

BTW....Nice Nixie Tube VM !!! Personally....I find the curved arabic font for numbers most pleasing....but....then again....I am at the end of the Bell Curve on this one !!!