Parallel‐coupled phase‐matched multiring optical filters

Abstract A periodic bandpass filter that is based on the phase‐matching principle and consists of several parallel‐coupled microrings is presented. The rings are identical in size; the coupling coefficients are chosen to provide maximally flat or equal ripple passband. Simulated filter characteristics exhibit steep roll‐off and large stopband rejection. Expressions are given to estimate the passband insertion loss and the stopband rejection level. The effects of loss and fabrication tolerances is examined. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 44: 536–540, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20689