矽線波導馬赫詹德延遲干涉儀(Delayed Mach-Zehnder Interferometer, DMZI),不僅可運用於色散(Chromatic Dispersion, CD)與光訊雜比(Optical Signal-to-noise Ratio, OSNR)監測,也可以應用在相位偏移鍵控(Phase Shift Keying, PSK)調變技 術。非理想型馬赫詹德延遲干涉儀在相位解調變時，會使得光隔離度下降,導致消光比變小及誤碼率表現不佳，同時也使得系統監測之靈敏度下降，此原因來自於干涉儀分光率不均，所以寬頻分光器在馬赫詹德延遲干涉儀器是非常重要的元件。
在本論文中，我們以多模干涉儀 (Multimode Interferometer, MMI)、馬赫-詹德方向耦合器(Mach-Zehnder Directional Coupler, MZDC)和 S 彎曲多模干涉儀(S-Bend Multimode Interferometer, S-Bend MMI)三種元件組合成矽線波導馬赫詹德延遲干涉儀，以應用在粗波分複用器(Coarse Wavelength Division Multiplexer, CWDM)，其中以 RSoft 與 Matlab 套裝商用軟體進行數值模擬分析並以理論基礎設計出矽線波導馬赫詹德方向耦合器、多模干涉儀和 S 彎曲多模干涉儀，使其具有寬頻譜的光學特性，其中MZDC更具有與波長不敏感與可任意分光率的分光功率器。
矽線波導光功率分光器尺寸為次微米，在彎曲波導結構會影響耦合相位，進而產生分光率的異常現象，所以設計元件時，我們特別考慮到彎曲結構所帶來的耦合效應，粗波分複用器系統適用的波長範圍在1280 nm與1320 nm之間，Channel Spacing 也設計在 10 nm。本論文的貢獻在於此矽線波導分波複用器之各種寬頻分光器的探討以及高光隔離度的可行性。

The delayed Mach-Zehnder interferometer (DMZI) can be applied to the chromatic dispersion (CD) monitoring and differential phase shift keying (DPSK) modulator/demodulator. The optical isolation of a non-ideal DMZI is reduced in the phase modulation, which causes the less extinction ratio and worse bit error rate besides less sensitive system monitoring. This optical isolation reduction mainly comes from the uneven spectral interferometer and implies the crucial property of broadband coupling in DMZI.
In this thesis, a silicon-wire based DMZI, composed by three broadband couplers of multimode interferometer, Mach-Zehnder directional coupler (MZDC) and S-Bend multimode interferometer is utilized to demonstrate the coarse wavelength division multiplexer (CWDM). The commercial software packages, Rsoft and Matlab, are taken for numerical simulation analysis on the wavelength independent coupler for the above three different kinds of optical power dividers.
Silicon-wire based optical power dividers is sub-micron size. The bending structure will affect the coupling phase and will be considered for broadband couplers to avoid the malfunction on splitting ratios. The operating wavelength range and channel spacing of CWDM are from 1280nm to 1320nm and 10 nm, respectively. The main contributions in this thesis are researching the different kinds of broadband couplers in CWDM applications to achieve higher possible isolations.

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