Recent progress of polymer-coated hollow fibers

High power capability and ruggedness make hollow fibers one of the leading candidates as a flexible delivery medium of infrared laser light. Cyclic-olefin polymer (COP) film is appropriate for all the wavelengths of 10.6-/spl mu/m CO/sub 2/, 2.94-/spl mu/m Er:YAG, and 1.06-/spl mu/m Nd:YAG lasers because of the small extinction coefficient of the polymer at these wavelengths. The COP also has relatively high temperature resistivity for around 150/spl deg/C that enables transmission of high peak energy, high power laser light. In this paper, firstly the fabrication process of the hollow fiber is briefly described. Then we report the transmission properties of the fibers for Nd:YAG, Er: YAG, and CO/sub 2/ lasers.