Fiber spot size: a simple method of calculation

The ability to integrate the Laguerre-Gauss functions in closed form is exploited to allow a simple but accurate evaluation of single-mode fiber spot size using Galerkin's method. The method avoids the need for numerical integration in a broad class of refractive-index profiles. Its simplicity depends on the use of a pattern-matching algorithm to avoid the numerical integration normally called for. The algorithm is very fast and gives exact results. The development of symbolic computer languages makes this approach especially easy. A symbolic program was used to predict the spot size and the far-field radiation pattern, and the results are compared with the exact values, getting excellent results. >

[1]  Petr Beckmann,et al.  Orthogonal polynomials for engineers and physicists , 1973 .

[2]  O. Georg.  Use of the orthogonal system of Laguerre-Gaussian functions in the theory of circularly symmetric optical waveguides. , 1982, Applied optics.

[3]  K Hotate,et al.  Measurement of refractive-index profile and transmission characteristics of a single-mode optical fiber from its exit-radiation pattern. , 1979, Applied optics.

[4]  Leonard G. Cohen,et al.  Single-mode fiber: From research and development to manufacturing , 1987, AT&T Technical Journal.

[5]  S. Banerjee,et al.  Chromatic dispersion in single-mode fibers with arbitrary index profiles: a simple method for exact numerical evaluation , 1989 .

[6]  Dietrich Marcuse,et al.  Gaussian approximation of the fundamental modes of graded-index fibers , 1978 .

[7]  C. D. Hussey,et al.  Approximate analytic forms for the propagation characteristics of single-mode optical fibres , 1985 .

[8]  Single Mode Fibre Characteristics , 1986 .

[9]  David N. Payne,et al.  Routine characterisation of single-mode fibres , 1976 .

[10]  W. A. Gambling,et al.  Simple characterisation factor for practical single-mode fibres , 1977 .

[11]  E. Neumann.  Single-mode fibers fundamentals , 1988 .

[12]  S. G. Mikhlin,et al.  Approximate methods for solution of differential and integral equations , 1970 .

[13]  R. L. Gallawa,et al.  Optical waveguide modes: an approximate solution using Galerkin's method with Hermite-Gauss basis functions , 1991 .

[14]  Ramanand Tewari,et al.  Dispersion-shifted dual-shape core fibers. Optimization based on spot size definitions , 1992 .

[15]  Dietrich Marcuse,et al.  Solution of the vector wave equation for general dielectric waveguides by the Galerkin method , 1992 .

[16]  W. Anderson,et al.  Spot size measurements for single-mode fibers - A comparison of four techniques , 1983, Journal of Lightwave Technology.

[17]  Charles Howard Henry,et al.  Solution of the scalar wave equation for arbitrarily shaped dielectric waveguides by two-dimensional Fourier analysis , 1989 .

[18]  Jean-Pierre Meunier,et al.  A general approach to the numerical determination of modal propagation constants and field distributions of optical fibres , 1981 .