The Big Green Thread (I'm gonna regret posting this in the morning)

[mixedgas]

Quote:
"
Should there be a waveplate in there too? Maybe an IR filter at the output. "

You only need the waveplate if the rod is unpolarized and or type 1 SHG is used. The traditional solution these days is to rotate a type II crystal 45' around its optical axis. This way the crystal acts as its own "waveplate". Nasty, cheap, robs power, but highly effective.

Steve

[mixedgas]

Ok, the first batch of optics I need, the ones to test the pumping in a improvised manor. arrived from China.

I need to lathe adapters for them, they are nice, but a non-standard size.

Steve

[krazer]

Sounds good, take lots of pictures

[macona]

I do have a bunch of waveplates and rotary mounts lying around for 1064. The KTPs I have are Type II, θ=90°; φ=23.5°

Got it home last night, here is a pic of the rod in it's mount. The thing is really heavy. Turns out the aluminum base plate is about 30mm thick.


IMG_3129 by macona, on Flickr

[mixedgas]

Macona, I'll get back to you with a list of mirrors to try shortly. See if the pump coupler mirrors are flat or if they have a radius on them. The radius would be facing the Vandate... Use a hene to determine this. If it comes to a focus, measure the focal length by finding where the hene is focused. I would try to do this without taking them out of the mounts. ON Z folds the two mirrors that determine the whole alignment ballgame are the first two either side of the lasing crystal. I would not want to disturb the pump optics, either.

If you have ever aligned a Z-fold before, you know what to do and can disregard the above.

Nice Vandate mount, how is it cooled?

Steve

[macona]

Ok. I will get out the HeNe tonight and check the mirrors.

The mount is water cooled. Water comes up one side from below through the top cover and back down the other side. You can see the two viton o-rings that seal the water passage between the blocks. I have a couple smaller thermoelectric water chillers to drive cool it.

[macona]

I pulled out the hene and the best I can tell is that the mirrors are dead flat.

[mixedgas]

I pulled out the hene and the best I can tell is that the mirrors are dead flat.

Good! Thats what I was hoping for.

Steve

[logsquared]

PPLN chip update.

Got my hands on one of m-green modules. Also bought a 5W FAC diode from Shawn.

Initial results are Very good! At room temp (67 deg) I was able to get 125mW at 1.5A and 250mW at 2A diode current.( highest my lab supply will go). The published specs are spot on so far! Divergence is very low. hard to tell what the exit diameter is, but the spot at 50' was round and about 3" in diameter.

Hopefully this week I will be able to machine a proper mount for everything and set it on a TEC. Prolly start a new thread for it as well. Just wanted to post an update.

[steve-o]

Piccys pleez !!!!!!! Cant wait to see this !!!!!