Anyone here collecting parts for, or working on a DPSS project?

[Wakrah]

Apologies for being late, but I have not tried yet. I have more than one FAP so was going to put power into it from both inputs. I have more than one of these, if you end up needing something. Not sure the answer to the beam path viewing question, since you bought this from SP, I would bet they would be able to answer a question or two, takes them some time to answer much of the time, other times quick.

 

[brianpe]

Progress Update:

I spent a fair amount of time designing a TEC controller...and then designing another one that could handle higher currents because the 5A I was sending to the TEC wasn't enough to keep the FAP cool. Yes, it is a little concerning that it may take more power to cool the FAP than to run it. And yes, I know I can buy TEC controllers but you either go down the rabbit hole or you don't. And I am going down this one.

I also bought a used spectrometer off eBay so I can tune the FAP wavelength. And it's a good thing I did. According to the Coherent datasheet I calculated I needed to keep the FAP at about 14 deg C for 808nm. But according to my spectrometer that's way too cold. The FAP was at about 800 nm and I had to warm it to 28 deg C for 808. That's a little concerning given that the operating temperature in the data sheet is 3-26 deg C. Too hot? Maybe these old FAPs off eBay don't quite match the modern data sheet.

So my FAP is wavelength tuned and I can maintain current and temperature for it. Time to see if I can get any 1064 out of the Spectra Physics head...and NOTHING. I bought a new set of IR viewers that handle higher powers but more importantly, glow red for 808 and green for 1064. No green. The next thing to attack here is the beam waist going into the YV04 crystal. The Spectra Physics head had a nice collimator that focused the fiber output into a nice 1mm dot onto the crystal. I had to replace this with a collimator that could take a SMA 905 connector, and I bought a focusable collimator from Edmund Optics. But when focused, the beam diameter is about 2x the size of the beam from the original. I've attached photos of the beam diameters at the focal points. Any idea if this is too big a diameter? Looks to be about 3mm here and everything I've read indicates I need a pretty small waist into the YV04. I don't know how big is too big but even if this were too big I am still surprised I'm not seeing any spontaneous 1064.

Original collimator:



Edmund Optics:


Anyone making progress on this front? If so please share.

 

[brianpe]

Another update: some level of success. Little white dot on the white IR target is a 1064nm laser beam at about 2 watts:



Glamor shot:



The whole apparatus:



Lots more to do. Only about 5% wall plug efficiency, need to convert to green, and need to convert to a z-fold so I can double-end pump. But hey! There is finally some pew-pew light coming out.

 

[kecked]

Great job. That’s not easy