Single-Mode Fiber Devices

Abstract

Optical fibers were once thought of strictly as a transmission medium. It was expected that any processing of the optical signal would take place outside of the fiber; either by conventional electronics, or by devices based on planar integrated optics. Over the years this situation has changed, as many optical components, that are made directly with single-mode fiber, have been reported. Such components include directional couplers, polarizers, phase modulators, polarization transformers, filters, and optical amplifiers. Most of these components require control over the state of polarization, and take advantage of recent improvements in polarization preserving fibers. At the same time there has been a steady improvement in single-mode fiber splicing techniques. It is thus becoming possible to think of fairly complex devices based on combinations of several inline single-mode fiber components.