Abstract

Intersecting waveguides are becoming an important guided wave element for integrated optics. The simplicity of the geometry, i.e., an absence of S-bends, makes it possible to achieve higher levels of switch integration with a switch element based on this geometry than is possible with directional couplers. Cross-connections between elements of integrated optical circuits are also possible because inter-waveguide coupling is a strong function of the crossing angle. No unified theory has thus far been constructed to explain all of the observed optical characteristics of various intersecting geometries. We report the derivation of a closed form expression which does quantitatively agree with experimental observations. As the results of our calculations show, intersecting waveguides have unique optical properties which cannot be predicted by seeking analogies with directional couplers.

© 1987 Optical Society of America