Compared to other transparent infrared fiber materials, ZBLAN fluoride glasses promise to be best suited for laser power
delivery in the 3μm wavelength region due to their high transmission and excellent mechanical flexibility. These claims
were demonstrated in a series of power handling tests of both straight and coiled fibers using an Er,Cr:YSGG laser
emitting a train of pulses of 150 μs duration at a repetition frequency of 20 Hz producing 7.5 W average power. Large
core fibers (450/510μm 0,2NA) are characterized by an attenuation of 0.02dB/m at 3μm and stay within 0.5°C from
ambient temperature when carrying full laser power. A 2-m fiber length prepared with bare cleaves has been tested for
over 23 hours, cumulating 1,140,000 shots of 1530 J/cm2 fluence while maintaining 90% transmission without any
measurable degradation. Coiling the fiber to 11 cm radius did not have an impact on power handling reliability. These
results show the potential of these highly transparent fibers in surgical laser delivery applications.
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