50W diode laser bar focusing.

I need little help.
I have http://www.laser2000.de/fileadmin/Produktdaten/FOL/Datenblaetter/FOL-CC-xxx-CW.pdf
50W module.
I need to focus this into 0,05mm spot from distance 100mm. How to do that. Is this possible? I have some basic knowledge but I am new to optics.
I have read lot of literature. I know that I need FAC lens.
Question is now witch. Dose this 2pcs 120°CYLINDER Line Lens Laser Line Lens | eBay works to get Fast Axis Divergence from 35 to 8 degree. So I can make beam where FAC=SAC. Then I think I can use normal lens and focus it into one spot.

murphy86 said:

I need to focus this into 0,05mm spot from distance 100mm... Is this possible?

Click to expand...

Absolutely not. The emitter size is your limitation here. You'd be quite lucky to get anything smaller than a couple mm.

Ok, but somehow they manage put this 50W beam to fiber witch is 100um diameter. How they do that?
If I put YAG crystal to beam path dose this work.
I know there is about 70% power loss but at least beam shape is ok?
I learned that 808nm will be absorbed in YAG quite short distance. So I think I need very thin Nd:YAG disc instead of long rod in xenon flash pumped laser?
Olso I have no idea about first side coating T=? . Second side should be HT @ 808nm and HR @ 1064nm.