<title>Hollow-tube-guide for UV-power laser beams</title>

Abstract

The use of ultraviolet lasers in medicine is expected to produce new surgical treatments. Basic experiments of the laser surgery with both KrF and XeCl excimer lasers have been completed. As is well known, visible and infrared beams are able to use ordinary quartz fiber. However, the optical fiber cannot be of use of power UV beam with excimer lasers. Some techniques about UV beams are needed. One of the techniques is the hollow tube with compound metal and polymer. This paper reports on the experimental results. The authors tried to transmit KrF and XeCl excimer laser beams by hollow tube guide. The hollow tube length is 1 meter. The delivery average power was 1.4W(KrF) and 3.8W(XeCl), the delivery energy was 7.0mJ/pulse(KrF) and 38mJ/pulse(XeCl), the peak power was 300kW(KrF) and 2.5MW(XeCl), the transmittance was 35%(KrF) and 49%(XeCl). The emitted beams are focused to ca.0.5mm diameter spot. Maximum peak power density and one pulse energy density of focused beam reached 700W/cm2(KrF), 1.9kW/cm2(XeCl) and 3.5J/pulse cm2(KrF), 19J/pulse cm2(XeCl). From the results, the hollow tube is possible as a UV power beams delivery system.