power meter discussion

[chimo]

[quote author=chimo link=1191040675/0#14 date=1191233082]I did this as well with interesting results.  One very key factor is the coating material on the peltier. The absorbtion and lack of susceptability to damage are important.

What did you use to coat your Peltier ?  What kinds of results did you have ?[/quote]

Well since you asked and since this was rough and dirty test, I used a very special fast drying black ink -------> a sharpie.  ;D  :

The benefits:  
-Very thin means a fairly good heat transfer to the peltier
-It's fast and redily available
-You can re-apply at will

The drawbacks:
-have no idea of the reflection/absorption for different wavelengths
-not sure about durability
-longevity
-susceptibility to damage from the beam (will it last long enough to get a stable reading???)

As far as results, it didn't record any results but I recall that the Glowtorch one generated about 70mV with my GB LD (@190mA) close behind (~60mV) and my DX 30 well behind those. I used one of the small double-stacked TECs.

 

[Archane]

This is an interesting idea, I just recently got a small pelt and if this pans out I would love to pick up another and use it in such a manner. I'd even be willing to set it all up and send it to someone that actually has a meter to test with to find out the drop ratio so I could figure out my lasers power as I test with them.


As far as the surface, I suggest a thin piece of black anodized aluminum, the anodizing should absorb alot of the power with little reflection and wouldn't be as suseptible to burning like the sharpie would.