SSY-1 Nd:YAG Laser
The ssy-1 as it known is a flashlamp pumped q-switched Nd:YAG laser that was used on tanks in WWII as a part of a laser rangefinder, and after the war ended a ton of them found their way onto the surplus market. Luckily, for once our tax dollars have done something useful to us, as almost anyone can get a moderately powerful yag laser for about $100 surplus (sites like ebay.com have an almost unending stream of them), that is well documented by the laser community.
System
A shot of the system the yag head is currently in, which was originally planned to be a CNC laser engraver, but after I damaged the flashlamp on my ssy-1 it got mothballed. The setup that damaged the flashlamp is also shown, the large bank of capacitors (about 200J worth) were just a little to much for the poor flashlamp and one day it exploded quite violently.
Output
A shot of the laser not focused on anything which, due to the extremely high peak power of the head, causes a small spark to form out of mid air, which makes a 'snap' sound. Also, a shot of the laser on a piece of copper plate which gives a green hue to the fireball.
A shot of a piece of black anodized aluminium just past the focal length so both the air ionisation and the fireball caused by the aluminum vaporizing, and a shot with the aluminum right at the focal point.
A shot of a piece of black foam and a LM555 time IC that was cause to hours of debugging.
More Information
The ssy-1 head is quite well documented, and a ton of information about it can be found on Sam's FAQ. One comment I will make is that there are a few factors limiting power for this laser. The pulse energy is limited to a few tens of millijoules by the internal q-switch (shots over about 25J input energy will damage the q-switch after a relatively small number of shots), but the q-switch can easily be removed to allow shots of to a few hundred joules in (which should give well over 1J output energy) before the flashlamp explodes. The average power is limited only by the cooling, and when I used the rod/q-switch out of my ssy-1 in my VersaPulse laser I was able to get well over a watt of output power without stressing the rod.
I can be contacted at contact@krazerlasers.com
