Couple light into photonic crystal fiber

[jlyu]

I have one hollow core fiber, the core is around 20um, Numerical Aperture is
0.03. The spot size of Ti:Sapphire laser is around 2~2.5mm. So I used focal
length 50mm. But only very few power can be achieved (6uw). I wonder
the reason. Could someone please give me some suggestions?

 

[Kim P. Hansen]

I have one hollow core fiber, the core is around 20um, Numerical Aperture is
0.03. The spot size of Ti:Sapphire laser is around 2~2.5mm. So I used focal
length 50mm. But only very few power can be achieved (6uw). I wonder
the reason. Could someone please give me some suggestions?

Hi There,

Maybe I can help you. Can you give a bit more information about the fiber you have? A 20µm core for a 800nm range hollow-core fibers sounds very big. Do you know if this is a 7 or a 19 cell design?

/Kim Hansen, NKT Photonics

 

[jlyu]

Actually, I do not think it belongs to 7 or 19 cell design. It is made by some other research group.

 

[Kim P. Hansen]

No worries. We would be happy to help even if the fiber is not made by us. Do you have a picture of the cross section of the fiber? Also, do you know what the loss in the fiber is at your laser wavelength?