JPS5583010A - Optical fiber for co2 laser surgical knife - Google Patents

Abstract

PURPOSE:To obtain the high-performance CO2 layser surgical knife by taper-cutting the incident end face of an optical fiber whose incident face is of the largest diameter and whose exit face is of the smallest diameter in such a manner that the incident angle becomes Brewster angle. CONSTITUTION:The incident end face 10a of the core 10 of an optical fiber for CO2 laser surgical knife is of the maximum diameter and the exit face is of the minimum diameter. The end face is so taper-cut that the incident angle phi of CO2 laser light 12 becomes Brewster angle. With this constitution, the end face 10a of a larger light receiving area makes the incidence of the laser light 12 easy and makes its energy density smaller, thus the layser light 12 enters the core 10 without any end face degradation and reflection loss and the high-density laser beam emits from the output end face of the smallest area, thereby providing the optical fiber for high-performance CO2 laser surgical knife. Here, the similar results are obtained even by affixing a germanium thin plate by which the incident angle of the CO2 laser beam becomes Brewster angle to the incident end face.