title: Bundled hollow optical fibers for transmission of high-peak-power Q-switched Nd:YAG laser pulses.
abstract: A hollow-fiber bundle was designed and used to deliver high-peak-power pulses from a Q-switched Nd:YAG laser. An 80 cm long bundle with a total diameter of 5.5 mm was composed of 37 glass capillaries with bore diameters of 0.7 mm. Beam-resizing optics with two lenses were used to couple the laser beam into the bundle. The measured coupling loss due to the limited aperture ratio of the bundle was 2.3 dB, and the transmission loss at wavelengths of 1064 and 532 nm was 0.3 dB. When an inert gas flowed through the bores of the capillaries, the maximum output pulse energy was 200 mJ, which was the limit of the laser used in the experiment. Hollow-fiber bundles withstand irradiation better than single hollow fibers and silica-glass optical fibers do. They are suitable for many dermatological applications because they can be used to irradiate a large area.
authors.affiliation: Department of Electrical Communications, Tohoku University, Sendai, Japan.
authors.forename: Ozgur
authors.initials: O
authors.lastname: Yilmaz
authors.forename: Mitsunobu
authors.initials: M
authors.lastname: Miyagi
authors.forename: Yuji
authors.initials: Y
authors.lastname: Matsuura