Hollow core fibers

Hollow-core photonic bandgap fibers use a microstructured cladding region with air holes to guide light in a hollow core.

The photonic bandgap guiding mechanism is fundamentally different from the traditional total internal reflection guiding principle. This new technology provides the basis for high power delivery without nonlinear effects or material damage. 

Other advantages with these fibers are that they are almost entirely bend-insensitive – they may be bent down <1 cm bend diameter without any change of optical transmission.

As more than 98% of the mode is confined in air, the fibers are also very radiation insensitive making them suitable for radiation hard environments. Applications includes:

Fiber optical gyroscopes
High power pulse transmission
Pulse compression
Gas lasers
Pocket cells
Sensing

High threshold power for nonlinear effects
Pure silica material
Core can be filled with gasses, particles etc
Extreme dispersion values for pulse compression/dispersion compensation
No Fresnel reflections at open fiber end
Polarization maintaining