Polariazation

[neutrino]

So when my diodes arrive from the recent group buy with Andy I want to combine two of the reds using the PBS in the PHR sled. How can I tell the polarization of the diodes? I was going to mount them in heatsinks and mark them up H and V so they can be swapped and changed if needed over time.

Cheers
Rich

[danielbriggs]

The way I do it is to mount the diode in a circular brass housing then in a larger aluminium block with a set screw to keep it in place. Wire it all up and fire it at the PBS cube. Then slowly rotate the brass housing, and the P and S polarisations will peak and trough as your rotate the module. Stop rotating when one is at a maximum (inferred to by having the other beam from the cube as dim as possible). Using a meter may help - but not needed. Then mark off on the unit. Repeat for the other module, but from the other side of cube (i.e. 90 deg to that)

There may be easier ways, but that works well for me

Ta,
Dan

[andy_con]

http://www.laser-man.co.uk/2006/inde...d=68&Itemid=66

[neutrino]

Thanks guys. I'll give it a go when everything arrives.

Can you combine green in the same way?

Rich

[andy_con]

combine two greens?

sure can i believe 90% are polarised

[ElektroFreak]

http://www.laser-man.co.uk/2006/inde...d=68&Itemid=66

Very helpful little aid you've put together there Andy! As can be seen in Andy's pics on the page he linked to above, the raw output beam of a laser diode (without any lenses) is elliptical. The polarization runs parallel to the widest axis, so if the wide axis (also called the fast axis) is horizontal, so is the polarization, and vice versa.

[andy_con]

thanks i do try

[neutrino]

Thanks guys. I'll make sure I remove the lenses first then.

Cheers
Rich