本研究展示了一種低成本的頻率調變連續波雷射測距(FMCW Lidar)系統，其中可調頻的單縱模雷射基於以PQ:PMMA製作的反射式體積布拉格光柵(VBG)窄化輸出光譜，並結合液晶元件作為相位調制元件達成頻率可調。雷射子系統被整合進一個光纖式FMCW Lidar系統中，採用Mach-Zehnder干涉儀架構，在10公尺的量測距離內達成2公分的距離解析度，距離量測極限以雷射光源之同調長度37公尺計算約為18.5公尺。實驗結果證實了低成本FMCW Lidar的可行性，並驗證了本系統在距離測量應用上的效能。

This thesis presents the development of a cost-effective frequency-modulated continuous-wave (FMCW) Lidar system featuring a frequency-tunable single longitudinal mode (SLM) laser. The laser is constructed using a PQ:PMMA-based reflective volume Bragg gratings (VBG) as the wavelength selective feedback element, and a Liquid crystal cell to modulate the optical path length for frequency tuning. Integrated into a fiber-based Mach-Zehnder interferometer architecture, the system achieves a ranging resolution of 2 cm over a 10-meter distance, with an estimated coherence length of 37 meters. Experimental results validate the feasibility of the proposed architecture and highlight its potential for low-cost high-resolution distance measurement applications.

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