Abstract

At the National Optics Institute we have developed a user friendly software system, BPM-CAD, to model integrated and fiber optical waveguide devices. The BPM-CAD is based on several numerical methods, the core of which is a 2-D and 3-D beam propagation method. Included is a correlation function method that gives modal properties such as propagation constants, relative mode weights, and mode eigenfunctions. To find modal properties of the more complicated waveguiding structures we also use a path integral method. This BPM-CAD system includes algorithms for solving the characteristic equation of planar multilayered structures and various types of fiber. Finally, to obtain the electric-field distribution of general electrode patterns for electrooptic devices, a mode projecting method is implemented. Each application has its own, multi-window data entry user interface with data editing abilities and geometrical device structure previewing. Acceptance of the edited and previewed data file starts the numerical procedure in a multiwindow, menu-driven graphical environment. Our research activities currently applying the BPM-CAD software include modal noise in short fiber sections, tapered fiber connector and, in integrated optics, the analysis of multi-mode branching structures and a Ti:LiNbO₃ integrated Doppler velocimeter.

© 1991 Optical Society of America