使用LCoS設計二維光纖陣列之3×6波長選擇開關

Abstract

波長選擇開關(WSS)為ROADM重要的核心器件，在現今對網速及頻寬需求越大的情況下，佔了很重要的一席之地。 本文使用液晶覆矽(LCoS)空間光調製器來設計一個3×6的WSS系統，利用Zemax光學設計軟體來設計整個光路架構，透過參數優化及光路校準的方式來讓理論耦合效率達到最好。 接著使用Matlab數學軟體執行迭代傅立葉演算法(IFTA)以生成相位全像圖，透過不均勻度優化演算法，將各個光場分開做補償，以將各輸入對應輸出之不均勻度都降到5%以下，提升了5~9%以上。 最後將相位全像圖輸入LCoS-SLM改變相位，實際架設光路以量測收光並計算損耗，本實驗之元件損耗約為12.04 dB~12.21 dB，系統總損耗約為23.5 dB~24.5 dB，耦合損耗約為1.5 dB~2.5 dB。

The Wavelength Selective Switch (WSS) is a critical core component of ROADM (Reconfigurable Optical Add/Drop Multiplexers), playing a significant role in the current era where the demand for network speed and bandwidth is continually increasing. This study utilizes a Liquid Crystal on Silicon(LCOS) Spatial Light Modulator (SLM) to design a 3×6 Wavelength Selective Switch(WSS) system. The entire optical pathway is designed using Zemax optical design software to optimize parameters and calibrate the optical path, achieving the best theoretical coupling efficiency. Subsequently, Matlab mathematical software is employed to execute the Iterative Fourier Transform Algorithm(IFTA) to generate phase hologram. Through the optimization algorithm for non-uniformity, each optical field is individually compensated, reducing the non-uniformity of each input-output correspondence to below 5%, thereby improving efficiency by 5-9%. Finally, the phase holograms are input into the LCOS-SLM to alter the phase. The optical path is practically set up to measure the received light and calculate the losses. The component loss in this experiment is approximately 12.04 dB to 12.21 dB, the total system loss is about 23.5 dB to 24.5 dB, and the coupling loss is around 1.5 dB to 2.5 dB.