PBS confusion

[Loonatic]

I'm a bit confused when you combine 2 beams using a PBS cube the beam that emerges is the total of the beams you put in isn't it ? (Or is it an average or some other figure due to refraction).

[Stuka]

Unfortunately, you'll probably lose at least a little bit with EVERY optic you use, be it mirrors (including the scanners), cubes, and dichro filters.

Because of this, the total power coming out of the PBS cube will probably be slighly less than the total of the separate lasers added together.
The trick, it would seem, is to minimize that loss at every step of the way.
So, if you hold your mouth just right while aligning the various optics, eveything should work out with minimal losses - until you decide to change something and have to do it all over again!!

[soforene]

...So, if you hold your mouth just right while aligning the various optics, eveything should work out with minimal losses....

You just know he's gonna ask how to hold it.

[Stuka]

That would probably do it!!

[loopee]

So how do you align the optics when it requires both hands to hold you're mouth just right

[Stuka]

LOTS of practice !!

All kidding aside -

Work with one optic at a time to get the best beam power out of it, then move to the next one. It may take a while to get everything aligned the first time around, but once it's done properly, periodic minor adjustments should be all that is needed (which is why you want to use adjustable mounts for all your optics).

And until you've done this a time or two, or ANYTIME there's a question where the beams might be going - wear laser safety goggles!!

[allthatwhichis]

ANYTIME there's a question where the beams might be going - wear laser safety goggles!!

Because you can't throw your hands up to block the beam if you are holding your mouth correctly.

[Loonatic]

Has any one got a PBS cube, a laser power meter, some different powered modules and some free time? I was thinking you try different combinations of input (to the cube) and measure the output, what percentage of the input will be the output be ?

[allthatwhichis]

rob (stanwax) has done, from what I understand, some extensive "research" on this subject. Rob...?

[Stuka]

Hooking up with some of the local fellows is a good suggestion.!

I don't thing there's going to be any "standard" configuration you can test for a catch-all guideline, since there's a LOT of variation in optics. You'll need to test the specific lasers you plan on using with specific PBS cubes designed for their wavelengths.

Also, my (limited) understanding of the theory behind the use of PBS cubes is you can't take just any 2 lasers of the same wavelength for it to work - they have to have very specific polarized output beam characteristics. The details of THAT, unfortunately, I can't be much help with, but hopefully some of the more knowledgeable folks will chime in with some more info...