本論文致力於研究波長分區多路復用濾波器(Wavelength-Division Multiplexing Filters)，以樹枝狀結構串接多個不同階數的級聯馬赫―曾德爾干涉多路復用器(cascaded Mach-Zehnder Interferometer multiplexer )，以達到低損耗且具有平坦通帶的波長通道分區輸出。
根據所需的分波效果，可藉由設計級聯馬赫―曾德爾干涉多路復用器來達成，計算各階所需的耦合係數與延遲項組合，可以任意設計具有寬通帶與寬阻帶的分波器，且維持兩輸出波形具有半個自由光譜範圍(Free Spectral Range, FSR)位移量的特徵，相鄰的通帶從不同通道輸出。
此外，由於在各階濾波器結構中所使用的定向耦合器因耦合係數易受波長影響，離開中心波長的區域有較高的串擾雜訊(crosstalk)，於是本論文中以絕熱消跡耦合器(Adiabatic Elimination Coupler)取代定向耦合器(Directional Coupler)，利用其耦合係數對波長調變較穩定的特性，降低級聯濾波器輸出波形的串擾，進一步使得使用絕熱消跡耦合器的波長分區多路復用濾波器具有較強的分光能力，最後比較耦合器取代前後的優缺點。

We present a new device of 4-channel wavelength-division multiplexing (de)multiplexer, which is less sensitive to wavelength. The flat pass-bands are provided by cascaded Mach-Zehnder interferometers, and the 1-to-4 wavelength (de)multiplexer device is based on a binary tree of cascaded Mach-Zehnder lattice filters. And we use a special algorithm to calculate and design CMZ filters with directional couplers or adiabatic elimination couplers. We made a comparison between filter with directional couplers and filter with adiabatic elimination couplers, and the former one is more sensitive to wavelength while the crosstalk of the later one remains <~-10dB at all wavelength.

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