Abstract: A method to improve the robustness of an elongated electrode used in an arc fusion apparatus for splicing optical fibers by reshaping the tip of the elongated electrode by electrolytic etching. The method involves reshaping the substantially sharp tip of the elongated electrode by immersing it as the anode in an electrolyte solution, the electrolyte solution is one capable of dissolving an oxidation product of the elongated electrode. Then a second electrode is provided at a predetermined distance from the elongated electrode in the electrolyte solution. Afterward, an electrical current is passed, or caused to flow, between the elongated electrode and the second electrode for a predetermined period of time through the electrolyte solution to reshape the substantially sharp tip of said elongated electrode into a predetermined profile having a substantially round tip.

Abstract: We have discovered that the strength of arc fusion splices in optical fiber can be adversely affected by particles (e.g., SiO.sub.2 particles) from the electrodes. Disclosed is a method of arc fusion splicing that can substantially increase the probability that a given fiber splice will meet a given strength requirement. The method comprises initiating the arc in a "cleaning" position selected such that the probability of incidence on the fibers of particles from the electrodes is relatively low, followed by changing the relative position between the electrodes with the arc therebetween and the fibers to the conventional "heating" position and forming the splice.

Abstract: We have discovered that the strength of arc fusion splices in optical fiber can be adversely affected by particles (e.g., SiO.sub.2 particles) from the electrodes. Disclosed is a method of arc fusion splicing that can substantially increase the probability that a given fiber splice will meet a given strength requirement. The method comprises initiating the arc in a "cleaning" position selected such that the probability of incidence on the fibers of particles from the electrodes is relatively low, followed by changing the relative position between the electrodes with the arc therebetween and the fibers to the conventional "heating" position and forming the splice.

Abstract: This invention is an apparatus which comprises a low reflection optical fiber termination. The apparatus comprises an optical fiber having a core, a cladding and a designated end. The core of the fiber has an effective refractive index N (exemplarily 1.484.+-.0.026). A terminator having a refractive index approximately equal to N (e.g. to within .+-.3.5%) is attached in such a manner that the terminator and the designated fiber end are in intimate contact. The closer the refractive index of the terminator is to the refractive index of the core of the fiber, the less back reflection occurs. A curable polymer having a high refractive index can be used to coat the terminator and a portion of the fiber. There is no need to polish, bend, cleave, twist or taper the end of the optical fiber prior to attaching the substrate to the optical fiber. Thus, the apparatus can be readily and inexpensively practiced not only in the factory but also in the field.

Abstract: The time required to collapse an OH-rich silica tube can be reduced significantly by subjecting the tube to a deuterium/hydrogen exchange prior to its collapse.