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Erbium Yag (Er:YAG) Fiber Delivery for Laser Surgery
Fluoride Glass & ZBLAN Fluoride Optical Fiber for Erbium Yag Energy Delivery
The Erbium:YAG (Er:YAG) laser has been evaluated and is used for precise tissue ablation in medical fields which do not require a flexible optical fiber delivery system, such as dermatology, dentistry, and ophthalmology. In these fields, the Er:YAG laser manufacturers have used an articulated arm or other means of delivering the Erbium:YAG (Er:YAG) wavelength to the tissue to be treated because no high quality Er:YAG fiber was available commercially. Several companies using different technologies have tried for years to make an infrared fiber to transmit at the Er:YAG wavelength. They include sapphire fibers, chalcogenide fibers, and hollow wave guide fibers.
The Problem with Current Erbium YAG (Er:YAG) Optical Fiber
Optical fibers transmitting at the Erbium window in medical lasers have not found much success because
in general, delivering 2,940 nm (Er:YAG) light into optical fiber is difficult. The Er:YAG wavelength is the wavelength of light most readily absorbed by water. For example, the water absorption coefficient difference between a Nd:YAG pulse and a Erbium YAG (Er:YAG) pulse is about 100,00 which is staggering. So in order to make a optical fiber that can successfully carry (or transmit) Erbium YAG (Er:YAG) light from the laser cavity to the tissue to be treated, one must carefully insure that no water moisture (OH-) will be present in the fiber. Otherwise the water in the Er:YAG fiber will absorb the energy and melt or damage the optical fiber. Furthermore the Erbium YAG fiber must be flexible and be able to sustain high power regimes.
The Ideal Erbium YAG (Er:YAG) Fiber
IRphotonics working in close cooperation with its customers has developed a ZBLAN fluoride optical fiber with very low moisture content which enables efficient transmission of the Erbium YAG (Er:YAG) wavelength. Using its patented enhanced ZBLAN fluoride fiber manufacturing process, IRphotonics has developped an Er:YAG fiber that is ideally suited for the transmission of Erbium:YAG energy. The transmittance at the Er:YAG wavelength is more 95%. The Er:YAG fiber is very flexible and has a power handling capacity of over 2 Joules or 5 MW / cm2 at the Erbium YAG window.
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