PMC-780-3-20ET-xxx

The main features of the fiber cable type PMC-780-3-20ET-xxx (also known as PMC-E-780-5.3-NA012-3-OPC.EC.TI-xxx-P) include

Fiber
The fiber is a polarization-maintaning, single-mode Panda fiber, defined by its NA and its cut-off wavelength. The nominal NA is 0.12 and is specified by the fiber manufacturer. Additionally the effective numerical aperture NAe² is measured for each fiber batch by Schäfter + Kirchhoff. The fiber has an effective numerical aperture NAe² of 0.08 and a cut-off wavelength λ_co of 770 nm. Maximum wavelength is 1100 nm. Besides the nominal cut-off wavelength λ_co, Schäfter + Kirchhoff also offers measured data for the cut-off wavelength for each individual fiber cable.

Fiber cable
The fiber cable has a 3 mm jacket in black with Kevlar strain-relief and a length of xx cm.

Fiber Connectors
The fiber cable is equipped with fiber connectors of type FC PC (0 deg polish, end cap, amagnetic, narrow key) All of the fiber connectors of type FC assembled by Schäfter + Kirchhoff have an alignment index (key). The narrow key (type "R") fiber connector has an alignment index (key) of 2 mm width.

End Caps
The fiber is equipped with an end cap connector. This means that a short length of fiber (< 300 µm) without a core is spliced onto the polarization-maintaining fiber. Without a fiber core to confine the beam, the mode field diameter of the beam already starts to diverge within the fiber end cap, significantly reducing the power density at the fiber end-face.

Amagnetic fiber connectors
Amagnetic fiber connectors are completely made of titanium and have a ceramic ferrule. This ensures that the relative permeability µ_r of the connector is near 1 (χ = 5·10^-5, µ_r = 1.00005), making it transparent to magnetic fields.