Advice needed Cr YAG

Hi Laserpointerforums Comunity,

I'm building laser pointers and yag lasers for a while now.
In all my builds I used assembled laser heads, but this time I'm building it from scratch.
My current project is a 200 joule pump energy nd yag pulse laser.
I got it all setup and tested, but i'm missing an passive q switch, therrefore i searched and found a company which sells cr yag crystals.
The company can produce crystals with 10 to 95% initial transmission.
I'm looking for a cr yag which would give me an optimized pulse performance, or in other words a good output with a highest possible peak power.
My question is what initial transmission would i need for that?

thanks in advance

If I recall correctly, the initial transmission is how much light is initially able to pass through the crystal. lower dopants and transmissives will make it easier to pump, but yield lower power output. standard Cr:YAG levels i'm not sure on, as I have never made one as they're not very common.

Hi ultimatekaiser,

thx for the reply.
So if I get this right, I should take an crystal with 80 to 95% initial transmission?
But in case of an 95% initial transmission cr yag, could there be an problem that the 200 joules aren't enough to pump it?

Assuming you have a good reflective cavity build and good clean appropriate mirrors, etc....that sounds like it should be enough. I'm not totally positive how high Cr's lasing threshold is. I'd have to look up its absorbtion too.

PhotonicsX said:

My current project is a 200 joule pump energy nd yag pulse laser.
I got it all setup and tested, but i'm missing an passive q switch, therrefore i searched and found a company which sells cr yag crystals.
The company can produce crystals with 10 to 95% initial transmission.
I'm looking for a cr yag which would give me an optimized pulse performance, or in other words a good output with a highest possible peak power.
My question is what initial transmission would i need for that?

Click to expand...

Your questions require a good research and calculations :wave:

I've never built the passive q-switch lasers, only had several experiments during the course many many years ago. Thus take everything with S&P.

The Koechner book 'Solid State Laser Engineering' discusses about the procedure to get a right value: a transmission of the absorber vs the output mirror transmission vs a pump power. The original scientific paper was by Degnan and published at IEEE J. Quantum Electron. QE-31, 1890 (1995)
Citing: "Typical transmission values range from 30% to 50%"

How did you get 200 Joules?