Oehrle R C
Appl Opt. 1979 Feb 15;18(4):496-500. doi: 10.1364/AO.18.000496.
A major difficulty in using a laser to draw optical fibers from a glass preform has been uniformally distributing the laser's energy around the melt zone. Several systems have evolved in recent years, but to date the most successful technique has been the off-axis rotating lens system (RLS). The inability of this device to structure efficiently and dynamically the heat zone longitudinally along the preform has restricted its use to preform of less than 8-mm diameter. A new technique reported here employs two orthogonal mounted mirrors, driven by galvanometers to distribute the laser energy around the preform. This system can be retrofitted into the RLS to replace the rotating lens element. The new system, the galvanometer scanning system (GSS), operates at ten times the rotational speed of the RLS and can instantaneously modify the melt zone. The ability of the GSS to enlarge the melt zone reduces the vaporization rate at the surface of the preform permitting efficient use of higher laser power. Experiments i dicate that fibers can be drawn from significantly larger preforms by using the expanded heat zone provided by the GSS.
使用激光从玻璃预制棒拉制光纤的一个主要困难在于如何使激光能量均匀分布在熔化区域周围。近年来已经发展出了几种系统，但迄今为止最成功的技术是离轴旋转透镜系统（RLS）。该装置无法沿预制棒纵向有效地动态构建热区，这限制了其仅适用于直径小于8毫米的预制棒。本文报道的一种新技术采用了两个由振镜驱动的正交安装的镜子，以在预制棒周围分布激光能量。该系统可以改装到RLS中以替换旋转透镜元件。新系统，即振镜扫描系统（GSS），运行速度是RLS转速的十倍，并且可以即时改变熔化区域。GSS扩大熔化区域的能力降低了预制棒表面的汽化速率，从而能够高效使用更高的激光功率。实验表明，通过使用GSS提供的扩展热区，可以从直径显著更大的预制棒拉制光纤。
