| Because of their perfect performance and potential application value inoptical communication systems, microring resonant (MRR) filters have been paidgreat attention of both home and abroad researchers who take great interests in theresearch of this field, and have become a hot research topic. Because of their someexcellent features, such as cheap cost, cohere structure, easy manufacture, highdensity integration, low insertion loss and low cross-talk, MRR filters have manyapplications in optical signal processing, filtering, multi/demultiplexing, routing,wavelength altering, modulating, switching, lasing and so on.In this thesis, in terms of the rectangular waveguide mode theory and thebasic principle of the MRR filter, the transmission characteristics of parallel-andseries-cascaded multiple MRR filters are analyzed in detail by the coupled modetheory (CMT) and the transfer matrix technique (TMT). On such basis, an M × Npolymer MRR filter array structure is presented, and the parameter optimizationand structural design are performed. We apply the directional couple theory of parallel waveguides to the bentcoupling between microring and channel or between two microrings, and presentthe bent coupling equation and the amplitude coupling ratio expression. Thisprovides a basic theory of the MRR filter research.In this thesis, the working principles and basic functions of the single MRRfilter are explained, and the transmission characteristics of single, and double-MRR filters are analyzed. The main purpose is to provide a theory basis and aresearch method for the MRR filter arrays which have more complex structures.Although the single MRR filter possesses some advantages including simplestructure and easy fabrication, it has some disadvantages, such as strongnon-resonant light in the output spectrum, high crosstalk and convexLorenz-shape response which needs accurate wavelength control.The advantage of the parallel-cascaded double or multiple MRR filter is thatit can form a flat box-like spectral response, so the set wavelength of the device isnot very strict, but the disadvantage of such devices is that it cannot drop thenon-resonant light intensity in the output spectrum obviously, therefore, it cannotdecrease the crosstalk effectively.The advantage of sries-cascaded double or multiple MRR filter is that it cangreating drop the non-resonant light intensity in the output spectrum and thecrosstalk, but the disadvantage of such devices is that the spectral response isundulant more or less, resulting in a harmful effect for the normal filtering of thedevices.On the basis of the preceding study, the transmission characteristics areanalyzed for a parallel-cascaded multiple MRR filter array ( 1 ×N) and for aseries-cascaded multiple MRR filter array ( M ×1) by using the CMT and theTMT. On such basis, a M × N MRR filter array is presented, its optimum designmethod is proposed, and its excellent features are described. This is the maincore section of this thesis.The M × N MRR filter array has both advantages of parallel-and series-cascaded MRR filters, and also overcomes their disadvantages. This device notonly forms a very flat spectral response, but also makes the non-resonant lightquite weak in the output spectrum by means of the optimizing its parameters, andhence it can decrease the crosstalk greatly. Therefore, the M × N MRR filterarray has better performances, and may become the ideal filtering device inoptical communication networks.This thesis designs a 5× 10 polymeric MRR filter array. Its 3-dB bandwidthof passband is about 0.35 nm, the minimum intensity of non-resonant light isdropped to –120 dB, and the bandwidth ratio between –1dB and –10dB is aboutIn this thesis, the working principles and basic functions of the single MRRfilter are explained, and the transmission characteristics of single, and double-MRR filters are analyzed. The main purpose is to provide a theory basis and aresearch method for the MRR filter arrays which have more complex structures.Although the single MRR filter possesses some advantages including simplestructure and easy fabrication, it has some disadvantages, such as strongnon-resonant light in the output spectrum, high crosstalk and convexLorenz-shape response which needs accurate wavelength control.The advantage of the parallel-cascaded double or multiple MRR filter is thatit can form a flat box-like spectral response, so the set wavelength of the device isnot very strict, but the disadvantage of such devices is that it cannot drop thenon-resonant light intensity in the output spectrum obviously, therefore, it cannotdecrease the crosstalk effectively.The advantage of sries-cascaded double or multiple MRR filter is that it cangreating drop the non-resonant light intensity in the output spectrum and thecrosstalk, but the disadvantage of such devices is that the spectral response isundulant more or less, resulting in a harmful effect for the normal filtering of thedevices.On the basis of the preceding study, the transmission characteristics areanalyzed for a parallel-cascaded multiple MRR filter array ( 1 ×N) and for aseries-cascaded multiple MRR filter array ( M ×1) by using the CMT and theTMT. On such basis, a M × N MRR filter array is presented, its optimum designmethod is proposed, and its excellent features are described. This is the maincore section of this thesis.The M × N MRR filter array has both advantages of parallel-and series-cascaded MRR filters, and also overcomes their disadvantages. This device notonly forms a very flat spectral response, but also makes the non-resonant lightquite weak in the output spectrum by means of the optimizing its parameters, andhence it can decrease the crosstalk greatly. Therefore, the M × N MRR filterarray has better performances, and may become the ideal filtering device inoptical communication networks.This thesis designs a 5× 10 polymeric MRR filter array. Its 3-dB bandwidthof passband is about 0.35 nm, the minimum intensity of non-resonant light isdropped to –120 dB, and the bandwidth ratio between –1dB and –10dB is about...
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