ABLATION WITH ONLINE MONITORING ON OPTICAL FIBER BY USING 157-NM (F2) LASER

摘要

The deep-ultraviolet 157-nm (F_(2)) laser, so called cold-ablation, has been proven to be a promising technique for microsculpting of wide-bandgap materials. The micromachining of optical fibers is essential for developing novel types of sensors with new micro-structures. In this paper, optical fiber with written fiber bragg gratings (FBGs) is ablated by 157-nm laser and the ablation is monitored online. The transmittance and reflectance spectrum are recorded during the whole ablation process. It is noted that the drifting of the reflective spectrum and the wavelength of FBGs is trivial, which probably prove the merit of cold ablation demonstrated by 157-nm laser. The transmittance spectrum shows the power decreasing while the ablation ongoing. By means of the online monitoring, the ablation of 157-nm laser is observable and controllable. Therefore, it is capable to achieve precise micromachining of optical fiber by 157-nm laser irradiation.