SSY1 ND YAG Divergence Question

OK, I've spent an hour searching the web today trying to find the approximate divergence of small ND YAG lasers such as the SSY1 which use close to a 3.5mm X 60mm rod, so far I'm not satisfied with what I'm finding. Does anyone know the approximate divergence of those small laser range finding YAG's?

I have just spent a bit finding out for you. Unfortunately I have had no luck either.

Depends on what cavity optics are on there - the ones on yours may be different from the SSY1. Measuring the beam directly may prove to be a bit of a pain due to the short pulse length and single shot nature of those heads.

Thanks, I did find mention that when the SSY1 is passively Q-switched the divergence is greater, but I am guessing having the Q switch shortens the pulse while at the same time increasing the power so much it more than makes up for it.

Alaskan said:

Thanks, I did find mention that when the SSY1 is passively Q-switched the divergence is greater, but I am guessing having the Q switch shortens the pulse while at the same time increasing the power so much it more than makes up for it.

Click to expand...

Why did I think the SSY1 had an active rotating prism type Q-switch? Must be thinking of some other small YAG...

Edit: Sam's FAQ says "a few mRad" divergence - not yet measured. Not terrible ... stick one of your big expanders on there

But yes, the Q-switch will make a big difference.

With Q-switch (Yellow, lamp current. Blue, lamp light. Pink, laser light):


Without Q-switch:


From this page: http://c4r0.elektroda.eu/_hv/index.php?page=lasers/ssy1

Isn't c4r0 a member here...?

Thank you so much, great. I'm a bit confused though, with the Q switch the graph shows a nice short duration spike, but I don't see that it is (edit: all that much) higher to indicate more peak power, I thought I'd see a big difference, is that a log scale?

Alaskan said:

Thank you so much, great. I'm a bit confused though, with the Q switch the graph shows a nice short duration spike, but I don't see that it is (edit: all that much) higher to indicate more peak power, I thought I'd see a big difference, is that a log scale?

Click to expand...

He's using double the pump energy with the Q-switch removed. 32J instead of 16J - that may explain it.

Plus this setup here isn't exactly the best way to accurately measure pulse energy:

oh, i am using my cell phone, loading that link is slow. flying to another base tonight.

Interesting web page on the SSY1

Laser YAG déclenché pompé par flash

Edit: Look at all the cool pages he has here: http://www.swissrocketman.fr/lasers-a-solides,fr,2,51.cfm

Alaskan said:

Interesting web page on the SSY1

Laser YAG déclenché pompé par flash

Edit: Look at all the cool pages he has here: lasers à solides rubis,YAG,verre néodyme,DPSS, déclenché,youtube,swissrocketman340

Click to expand...

Yep, discovered his page ages ago, I'm sure I posted it somewhere. Lots of cool stuff!

FYI, he also has a YouTube channel
https://www.youtube.com/user/rocketman340

He's the guy I mentioned in another thread that's been working on the TEA CO2 pumped dye laser, using the light from air breakdown caused by the CO2 laser to pump the dye.

Oh, I have watched his videos many times before. I didn't notice the URL.

I've had the luxury of being able to search the net all day long for several days while waiting for the next flight out of this base, a whole week between flights to where I need to go, so googling information, when I can... the internet is up and down here terribly, but sometimes up for hours, yay! So, I found his web page when YouTubing YAG's. My next question to find the answer to is to understand how the power output and pulse width of a SSY1 YAG is changed when removing the passive Q-switches. I think I saw where the thing puts out ten times more power due to the power being concentrated in such a short pulse when using a Q switch, trying to confirm. If anyone knows, please jump in.

Yep, more info just found:

I no sooner post this and I find that without the Q-Switch the rod just lases and outputs power as long as the pulsed light from the flash tube is active, so the pulse width then depends upon how long the flash is present, another subject to chase down now to know what determines how long a flash is but I suspect that is determined by the particular flash tube, the amount of capacitance and the choice of inductor used for the flash circuit, unless you have some fancy circuit board which can control the pulse width to the flash tube.

So, I'm digging for info on the above, and I need to find how many mJ of 1064nm one of these YAG rods can produce without a Q-Switch. Also, I need to know how the output might be polarized, or not.... seeking that info, so I re-welcome anyone who can answer those questions to jump right in, if you feel inclined, could save me some time searching, but I will keep looking in the mean time, will post if I find the info.

I know with those 532nm laserscopes, the Q-switch helped tremendously with the power output compared to without. I'm guessing it would be same with the YAG rod.

I'm investigating optic choppers to Q switch that way, but getting conflicting info regarding whether that method is a good way to go or not.