在本篇論文中，將利用週期呈高斯分布的無足化光柵結構（apodized grating）於單模波導管中，設計一個具禁止帶（stop band）反射頻譜的光濾波器，並以有限差分時域法（FDTD）來進行二維結構的模擬與分析。由模擬數據可知，在波導管中增加無足化光柵的對數時，可以得到較陡峭的反射頻帶，而且中心波長的反射率會更趨近1。我們接著將無足化光柵結構應用於雙模干涉分波多工器（TMI-WDM）中，探討兩種波導管結構：具側邊鋸齒形光柵與內洞型光柵。研究結果顯示，無足化光柵結構雖然會增加TMI-WDM所須的耦合長度，但是能有效地降低中心波長周邊的反射波，以得到具有平坦側頻（side-lobe）的反射頻譜。希望藉由此特性可以增加TMI-WDM分波的效能。

　An accurate design for an apodized integrated optical wavelength filter using Gaussian-distribution sidewall Bragg gratings is proposed, 2-dimensionally simulated and analyzed using the finite-difference time-domain method (FDTD). It is verified that for various grating, the central wavelengths of the reflection bands are all fixed at designed 1.55 μm with the side lobes well suppressed. Then we apply the apodized grating to the TMI-WDM with different waveguide structures： the dispersive tooth-shaped grating and the central hole-etched grating. The simulated results prove that the apodized grating will increase the coupling length in TMI-WDM, but it can suppress the side-lobes additionally. Therefore, the efficiency of the WDM could be improved through the apodized gratings.

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