Measurement of Optical Waveguide Coupling Coefficients using Multiple Waveguide Systems.

A method for simply and accurately determining the coupling coefficient between integrated optical waveguides is presented. Measurement of only a few features of the output power distribution from a linear array of identical guides is required. The result is most accurate for long samples, but approximates the coupling coefficient to well within a few percent even for samples shorter than one two-guide coupling length. Since waveguides in the array would be fabricated in the same way, perhaps on the same substrate, as the device structures of interest, the method ought to be useful and convenient one for device designers.