CO₂Laser Assisted Fabrication of Micro-lensed Single-mode Optical Fiber

Abstract

This paper reports the fabrication of various micro-lensed single-mode optical fibers through the use of an enhanced peak power <TEX>$CO_2$</TEX> laser beam. The end faces of the optical fibers are exposed to the <TEX>$CO_2$</TEX> laser beam to form convex, concave, and conical shape optical fiber tips. Peak power of the <TEX>$CO_2$</TEX> laser beam was varied from 0.8 W to 1.5 W depending on the shape of the optical fiber tip. We also discover the dependence of the angle of the optical fiber tip on the rotation angle and the number of <TEX>$CO_2$</TEX> laser irradiations. The angle shows an increasing trend with both these parameters. We achieve a wide range of lenticular fibers with end face angle varying from <TEX>$4.47^{\circ}$</TEX> to <TEX>$8.13^{\circ}$</TEX>. Furthermore, we investigate the emission pattern of light from the developed micro-lensed fibers. The proposed <TEX>$CO_2$</TEX> laser based optical fiber reshaping technique shows great consistency, and thus is suitable for commercial applications.