anyone seen these and how are they used

http://o-like.com/b2b_cpinfo.asp?id=943

http://o-like.com/b2b_cpinfo.asp?id=941

They're frequency doubling crystals. In DPSS green lasers they convert the 1064nm IR to 532nm green.

You would get these if you want to experiment with homebrew DPSS.

cheers,
kernelpanic

[edit] Actually the second one is YVO4 which turns the 808nm IR into 1064nm. Then the KTP would do the 1064->532nm. With one of each and an 808nm laser, you could build a green labbie. [/edit]

dont those have to be Nd doped to lase?

The YVO4 does(Neodymium). The KTP does not.

cheers,
kernelpanic

Lawl @ Nd:KTP. I don't think it would work