Modeling of rough-surface effects in an optical turning mirror using the finite-difference time-domain method

Author

Lee, Shing Man ; Chew, Weng Cho ; Moghaddam, Mahta ; Nasir, Muhammad A. ; Chuang, Shun-Lien ; Herrick, Robert W. ; Balestra, Chester L.

Author_Institution

Dept. of Electr. & Comput. Eng., Illinois Univ., Urbana, IL, USA

Volume

9

Issue

11

fYear

1991

fDate

11/1/1991 12:00:00 AM

Firstpage

1471

Lastpage

1480

Abstract

A finite-difference time-domain (FDTD) method is applied to calculate the forward-reflected and back-reflected powers of a guided mode from a rough turning mirror in a bent waveguide of a high-power laser array. By segmenting this large problem into a number of smaller problems, the simulation region can be shrunk to a small area containing only the details of the rough-surface mirror. By launching the incident wave judiciously, the computation time grows linearly with the length of the mirror. A farfield transformation of the calculated time-domain scattered field yields forward-reflected and back-reflected powers. The computer time needed to analyze this large turning-mirror system is reduced to about 3 min of CRAY time, compared to several hours for a brute-force approach using a full mesh

Keywords

difference equations; digital simulation; laser accessories; mirrors; optical waveguide theory; physics computing; semiconductor laser arrays; surface topography; back-reflected powers; bent waveguide; calculated time-domain scattered field; computation time; computer time; farfield transformation; finite-difference time-domain method; forward reflected powers; guided mode; high-power laser array; incident wave; optical turning mirror; rough turning mirror; rough-surface effects; simulation region; Finite difference methods; Laser modes; Mirrors; Optical arrays; Optical scattering; Optical waveguides; Power lasers; Time domain analysis; Turning; Waveguide lasers;

fLanguage

English

Journal_Title

Lightwave Technology, Journal of

Publisher

ieee

ISSN

0733-8724

Type

jour

DOI

10.1109/50.97635

Filename

97635