Tapering and Metallizing Optical Fibers by Immersion in Buffered Aqueous Solution with Different Molar Ratios

Abstract

In this work, three basic techniques for tapering an optical fiber were presented and discussed. These techniques are meniscus etching, selective etching and pulling. They depend on immersion of the optical fiber in a buffered HF solution (BHF) with different volume ratio of [40%-NH4F aqueous sol.]:[50%-HF acid]:[H2O] at 25°C. The dependencies of dissolution rates and cone angle on the ratio of [40%-NH4F aqueous sol.] were determined. The dependency of cone angle on the difference in refractive index was determined too.