Silica Optical Fiber Technology for Devices and Components: Design, Fabrication, and International Standards

CHAPTER TWO

Review on Single-Mode Fiber Design and International Standards

2.1   OPTICAL MODES IN CYLINDRICAL WAVEGUIDES

Optical fiber carries information over electromagnetic wave and it is one of dielectric waveguides. In optical fiber act, we are dealing with electromagnetic wave in the infrared range, say from 0.8 to 1.6 μm for optical communications, and we are concerned with its propagation along a cylindrical dielectric waveguide comprised of silica glass core and cladding. In order to understand the propagation properties of light over an optical fiber, it is, therefore, necessary to review the electromagnetic wave theory in a dielectric medium.

First, we will review Maxwell’s equations in an infinite dielectric medium, and then try to find the guided electromagnetic waves defined by a cylindrical dielectric waveguide with a set of characteristic propagation properties, which are called modes.

Maxwell’s equations 2.1–2.4 in an infinite medium are coupled partial differential equations of four physical quantities, , , , and , for given source terms ρ and . In MKS unit those fields ...